SECTION XVI_Disease in captive wild mammals and birds

NEOPLASMS

The occurrence of true neoplasms in domesticated animals has always been

well known and thoroughly studied while for beasts in the wild the data

has been fragmentary. That tumors exist in natural environment has been

accepted upon the testimony of hunters but there is an impression, and

nothing more, of their extreme scarcity probably because only younger

vigorous animals come to the attention of the sportsman or collector.

This matter will of course not be settled until some natural historian

with a knowledge of pathology, makes a survey of a large number of

specimens taken during a collecting expedition. Observations in

menageries are valuable to the extent that they show what tumors may

occur, the orders most commonly affected and the incidence under captive

conditions. It is unfortunate that too seldom do we know the history of

our specimens in regard to the age, manner of capture or breeding, data

which if at our disposal would permit of a very fair idea of the

probable incidence in the wild and of the effect of captivity. Some

observations in this direction are however possible by using the figures

of known captivity and breeding.

The facts gleaned from a study of neoplasms under captive conditions may

be of interest to the experimental pathologist, especially when

considering the relation of the origin from the embryological layers. I

have tabulated this with great care, using Jordan’s[90] table for the

source of the various tissues, and further have studied the destination

of metastatic emboli in terms of the blastoderm.

The following observations are based entirely upon our own data for

while it might be valuable to include the cases in the literature their

descriptions are often so meagre that they would not combine readily

with our records. Plimmer, Seligmann, and Murray have published in the

_Proceedings of the London Zoological Society_ since 1903, their annual

report of the pathological service in which they have recorded very many

interesting tumors. So too from time to time Harlow Brooks and W. R.

Blair in the _Annual Report of the New York Zoological Park_, have

presented cases occurring in their service. Joest [91] discusses tumors

in the lower animals in a broad way and analyzes their incidence and

characters. C. Y. White and I [92] have already published articles on

this subject. Numerous single references may be found in the _Jahresber.

der Veterinär-Medicin_.

In so far as the incidence of tumors in wild animals is concerned this

literature can scarcely give an adequate measurement but it would seem

that they are less than in domestic varieties. Exact figures for the

occurrence of tumors in the latter seem not available in the literature,

but one can find that in the Prussian army horses about one hundred are

observed each year. In our 5,365 specimens collected during nineteen

years, 94 tumors in 92 animals have been found, 1.7 per cent. or about

one in every sixty specimens, not at all a low figure. If one were to

include all fibromata of the feet and the blood collections to which the

name angioma might be applied, this incidence would be greater; they are

excluded because few in number and vague in history; only one true

angioma was seen.

The gross and microscopical appearances of tumors in the lower animals

are essentially the same as one encounters in human beings or at least

it is possible to apply the pathological nomenclature used in human

medicine to all the neoplasms we have discovered. There is appended a

list of all the animals and their tumors, a table of zoological orders,

tumors and organs (Table 21) and an analytical table of the histological

data. (Table 22)

TABLE 21.

_Table of Orders and Families Showing Type of Tumor and Principal Organ

of Origin._

═══════════════════╤═══════╤═══════╤═════════╤══════╤══════════╤══════

Order Family │Fibroma│Osteoma│Chondroma│Lipoma│Myoma and │Glioma

│ │ │ │ │Fibromyoma│

│ │ │ │ │ │

───────────────────┼───────┼───────┼─────────┼──────┼──────────┼──────

„ „ │ „ │ „ │ „ │ „ │ „ │ „

│ │ │ │ │ │

Primates, │ │ │ │ │ │

Cercopithecidæ │ │ │ │ │ │

Cebidæ │ │ │ │ │ │

│ │ │ │ │ │

Lemures, Lemuridæ │ │ │ │ │ │

│ │ │ │ │ │

Carnivora, Felidæ │ │ │ 1│ │ │

│ │ │ │ │ │

Viverridæ │ │ │ │ │ │

Canidæ │ │ │ │ │ │

Procyonidæ │ │ │ │ │ │

Ursidæ │ │ │ │ │ │

│ │ │ │ │ │

Phocidæ │ │ │ │ │ │

│ │ │ │ │ │

Rodentia, Sciuridæ │ │ 1│ │ │ │

Muridæ │ │ │ │ │ │

Heteromyidæ │ │ │ │ │ │

│ │ │ │ │ │

Octodontidæ │ │ │ │ │ │

Hystricidæ │ │ │ │ │ │

Dasyproctidæ │ │ │ │ │ │

│ │ │ │ │ │

Proboscidea │ │ │ │ │ 1│

Ungulata, Equidæ │ 1│ │ │ │ │

Bovidæ │ │ │ │ │ 1│

Cervidæ │ │ │ │ │ │

Camelidæ │ │ │ │ │ │

Suidæ │ │ │ │ │ │

Edentata, │ │ │ │ │ 1│

Dasypodidæ │ │ │ │ │ │

Marsupialia, │ │ │ │ │ │

Didelphyidæ │ │ │ │ │ │

Dasyuridæ │ │ │ │ │ │

Peramelidæ │ │ │ │ │ │

Macropodidæ │ │ │ │ │ │

Passeres, Turdidæ │ │ │ │ │ │

Crateropodidæ│ │ │ │ │ │

Tanagridæ │ │ │ │ 1│ │

Fringillidæ │ │ │ │ 1│ │

Icteridæ │ │ │ │ │ │

Striges, Bubonidæ │ │ │ │ │ │

Psittaci, Loridæ │ │ │ │ │ │

Cacatuidæ │ │ │ │ 2│ │

Psittacidæ │ │ │ │ 3│ │ 1

│ │ │ │ │ │

Accipitres, │ │ │ │ 1│ │

Falconidæ │ │ │ │ │ │

Columbæ, Columbidæ │ │ │ │ │ │

Galli, Phasianidæ │ │ │ │ │ │

Fulicariæ, Rallidæ │ │ │ │ │ │

Anseres, Anatidæ │ 1│ │ │ │ │

Struthiones, Rheidæ│ │ │ │ │ │

Total │ 2│ 1│ 1│ 8│ 3│ 1

───────────────────┴───────┴───────┴─────────┴──────┴──────────┴──────

═══════════════════╤═══════╤════════════╤═══════╤═════════╤═══════════

Order Family │Angioma│Endothelioma│Sarcoma│Papilloma│Epithelioma

│ │ │ │ │

───────────────────┼───────┼────────────┼───────┼─────────┼───────────

„ „ │ „ │ „ │ „ │ „ │ „

│ │ │ │ │

Primates, │ │ │ │ │

Cercopithecidæ │ │ │ │ │

Cebidæ │ │ │ │ │

│ │ │ │ │

Lemures, Lemuridæ │ │ │ │ │

│ │ │ │ │

Carnivora, Felidæ │ 1│ 1│ │ │

│ │ │ │ │

Viverridæ │ │ │ │ │

Canidæ │ │ │ 1│ │

Procyonidæ │ │ │ │ │

Ursidæ │ │ │ │ │ 1

│ │ │ │ │

Phocidæ │ │ │ │ │

│ │ │ │ │

Rodentia, Sciuridæ │ │ │ │ │

Muridæ │ │ │ 2│ │

Heteromyidæ │ │ │ 1│ │

│ │ │ │ │

Octodontidæ │ │ │ 1│ │

Hystricidæ │ │ │ │ │

Dasyproctidæ │ │ │ │ │

│ │ │ │ │

Proboscidea │ │ │ │ │

Ungulata, Equidæ │ │ │ │ │

Bovidæ │ │ │ 1│ │

Cervidæ │ │ │ │ │

Camelidæ │ │ │ │ │

Suidæ │ │ │ │ │

Edentata, │ │ │ │ │

Dasypodidæ │ │ │ │ │

Marsupialia, │ │ │ │ │

Didelphyidæ │ │ │ │ │

Dasyuridæ │ │ │ │ │ 1

Peramelidæ │ │ │ │ │

Macropodidæ │ │ │ │ │

Passeres, Turdidæ │ │ │ │ │

Crateropodidæ│ │ │ │ │

Tanagridæ │ │ │ │ │

Fringillidæ │ │ │ │ │

Icteridæ │ │ │ │ │

Striges, Bubonidæ │ │ │ │ 1│

Psittaci, Loridæ │ │ │ │ │

Cacatuidæ │ │ │ │ │

Psittacidæ │ │ │ 7│ │ 1

│ │ │ │ │

Accipitres, │ │ │ 1│ │

Falconidæ │ │ │ │ │

Columbæ, Columbidæ │ │ │ 1│ │

Galli, Phasianidæ │ │ │ │ │

Fulicariæ, Rallidæ │ │ 1│ │ │

Anseres, Anatidæ │ │ │ 1│ │

Struthiones, Rheidæ│ │ │ │ │

Total │ 1│ 2│ 16│ 1│ 3

───────────────────┴───────┴────────────┴───────┴─────────┴───────────

═══════════════════╤═══════╤═════════╤═══════════╤═════════════╤══════

Order Family │Adenoma│Carcinoma│ Chorion- │Hypernephroma│Mixed

│ │ │epithelioma│ │Tumors

│ │ │ │ │

───────────────────┼───────┼─────────┼───────────┼─────────────┼──────

„ „ │ „ │ „ │ „ │ „ │ „

│ │ │ │ │

Primates, │ 1│ │ │ │

Cercopithecidæ │ │ │ │ │

Cebidæ │ │ │ │ 1│

│ │ │ │ │

Lemures, Lemuridæ │ 1│ │ │ │

│ │ │ │ │

Carnivora, Felidæ │ 2│ 1│ │ │

│ │ │ │ │

Viverridæ │ │ 2│ │ │

Canidæ │ 3│ 1│ │ │ 1

Procyonidæ │ 1│ │ │ │

Ursidæ │ │ 2│ │ │

│ │ │ │ │

Phocidæ │ │ │ │ 1│

│ │ │ │ │

Rodentia, Sciuridæ │ 1│ │ │ 1│

Muridæ │ │ 3│ │ │

Heteromyidæ │ │ │ │ │

│ │ │ │ │

Octodontidæ │ │ │ │ │

Hystricidæ │ │ │ 1│ │

Dasyproctidæ │ │ 1│ │ │

│ │ │ │ │

Proboscidea │ │ │ │ │

Ungulata, Equidæ │ │ │ │ │

Bovidæ │ │ │ │ │

Cervidæ │ 1│ │ │ │

Camelidæ │ │ 1│ │ │

Suidæ │ │ 1│ │ │

Edentata, │ │ │ │ │

Dasypodidæ │ │ │ │ │

Marsupialia, │ 1│ 1│ │ │

Didelphyidæ │ │ │ │ │

Dasyuridæ │ │ 1│ │ │

Peramelidæ │ │ 1│ │ │

Macropodidæ │ │ 2│ │ │

Passeres, Turdidæ │ │ │ │ 1│

Crateropodidæ│ 1│ │ │ │

Tanagridæ │ │ │ │ │

Fringillidæ │ │ 2│ │ │

Icteridæ │ │ │ │ 1│

Striges, Bubonidæ │ │ │ │ │

Psittaci, Loridæ │ │ 1│ │ │

Cacatuidæ │ │ │ │ │

Psittacidæ │ 5│ 4│ │ 1│ 1

│ │ │ │ │

Accipitres, │ │ │ │ │

Falconidæ │ │ │ │ │

Columbæ, Columbidæ │ │ │ │ │

Galli, Phasianidæ │ │ 1│ │ │

Fulicariæ, Rallidæ │ │ │ │ │

Anseres, Anatidæ │ 1│ │ │ 1│

Struthiones, Rheidæ│ 1│ │ │ │

Total │ 19│ 25│ 1│ 7│ 2

───────────────────┴───────┴─────────┴───────────┴─────────────┴──────

═══════════════════╤═══════════════════════════════════════════

Order Family │ Organic Source of Tumor

│

───────────────────┼────┬──────┬───────┬──────┬──────┬─────────

„ „ │Lung│Muscle│Thyroid│Uterus│Kidney│Bone and

│ │ │ │ │ │Cartilage

───────────────────┼────┼──────┼───────┼──────┼──────┼─────────

Primates, │ │ │ │ │ │

Cercopithecidæ │ │ │ │ │ │

Cebidæ │ │ │ │ │ │

│ │ │ │ │ │

Lemures, Lemuridæ │ │ │ │ │ │

│ │ │ │ │ │

Carnivora, Felidæ │ │ │ │ 2│ │ 1

│ │ │ │ │ │

Viverridæ │ 1│ │ │ │ │

Canidæ │ │ │ 3│ │ │

Procyonidæ │ │ │ │ │ │

Ursidæ │ │ │ │ │ │

│ │ │ │ │ │

Phocidæ │ │ │ │ │ │

│ │ │ │ │ │

Rodentia, Sciuridæ │ │ │ │ │ 1│ 1

Muridæ │ │ 3│ │ │ │

Heteromyidæ │ │ │ │ │ │

│ │ │ │ │ │

Octodontidæ │ │ │ 1│ │ │

Hystricidæ │ │ │ │ 1│ │

Dasyproctidæ │ │ │ │ │ │

│ │ │ │ │ │

Proboscidea │ │ │ │ 1│ │

Ungulata, Equidæ │ │ │ │ │ │

Bovidæ │ │ │ │ 1│ │ 1

Cervidæ │ │ │ │ │ │

Camelidæ │ │ │ │ │ │

Suidæ │ │ │ │ 1│ │

Edentata, │ │ │ │ 1│ │

Dasypodidæ │ │ │ │ │ │

Marsupialia, │ │ │ │ │ 1│

Didelphyidæ │ │ │ │ │ │

Dasyuridæ │ │ │ │ │ │

Peramelidæ │ 1│ │ │ │ │

Macropodidæ │ 1│ │ │ │ │

Passeres, Turdidæ │ │ │ │ │ 1│

Crateropodidæ│ │ │ │ │ 1│

Tanagridæ │ │ │ │ │ │

Fringillidæ │ │ │ │ │ 2│

Icteridæ │ │ │ │ │ 1│

Striges, Bubonidæ │ │ │ │ │ │

Psittaci, Loridæ │ 1│ │ │ │ │

Cacatuidæ │ │ │ │ │ │

Psittacidæ │ │ 2│ 1│ 1│ 5│

│ │ │ │ │ │

Accipitres, │ │ │ │ │ │

Falconidæ │ │ │ │ │ │

Columbæ, Columbidæ │ │ │ │ │ 1│

Galli, Phasianidæ │ │ │ │ │ │

Fulicariæ, Rallidæ │ │ │ │ │ │ 1

Anseres, Anatidæ │ │ 1│ │ │ 1│ 1

Struthiones, Rheidæ│ │ │ │ │ │

───────────────────┼────┼──────┼───────┼──────┼──────┼─────────

Total │ 4│ 6│ 5│ 8│ 14│ 5

───────────────────┴────┴──────┴───────┴──────┴──────┴─────────

═══════════════════╤═══════════════════════════════════════════════

Order Family │ Organic Source of Tumor

│

───────────────────┼────────────────┬──────┬──────────┬──────┬─────

„ „ │Gastrointestinal│Liver,│Peritoneum│Lymph │Mamma

│ Tract │ &c. │ │Tissue│

───────────────────┼────────────────┼──────┼──────────┼──────┼─────

Primates, │ 1│ │ │ │

Cercopithecidæ │ │ │ │ │

Cebidæ │ │ │ │ │

│ │ │ │ │

Lemures, Lemuridæ │ │ │ │ │

│ │ │ │ │

Carnivora, Felidæ │ │ 1│ │ 1│

│ │ │ │ │

Viverridæ │ 1│ │ │ │

Canidæ │ │ 2│ │ │

Procyonidæ │ │ │ │ │

Ursidæ │ │ │ │ │ 1

│ │ │ │ │

Phocidæ │ │ │ │ │

│ │ │ │ │

Rodentia, Sciuridæ │ │ 1│ │ │

Muridæ │ │ │ │ │ 2

Heteromyidæ │ │ │ │ │

│ │ │ │ │

Octodontidæ │ │ │ │ │

Hystricidæ │ │ │ │ │

Dasyproctidæ │ │ │ │ │

│ │ │ │ │

Proboscidea │ │ │ │ │

Ungulata, Equidæ │ │ │ 1│ │

Bovidæ │ │ │ │ 1│

Cervidæ │ │ 1│ │ │

Camelidæ │ │ 1│ │ │

Suidæ │ │ │ │ │

Edentata, │ │ │ │ │

Dasypodidæ │ │ │ │ │

Marsupialia, │ │ │ │ │ 1

Didelphyidæ │ │ │ │ │

Dasyuridæ │ 1│ │ │ │

Peramelidæ │ │ │ │ │

Macropodidæ │ 1│ │ │ │

Passeres, Turdidæ │ │ │ │ │

Crateropodidæ│ │ │ │ │

Tanagridæ │ │ │ │ │

Fringillidæ │ │ │ │ │

Icteridæ │ │ │ │ │

Striges, Bubonidæ │ 1│ │ │ │

Psittaci, Loridæ │ │ │ │ │

Cacatuidæ │ │ │ │ │

Psittacidæ │ 1│ 3│ │ │

│ │ │ │ │

Accipitres, │ │ │ 1│ │

Falconidæ │ │ │ │ │

Columbæ, Columbidæ │ │ │ │ │

Galli, Phasianidæ │ │ │ │ │

Fulicariæ, Rallidæ │ │ │ │ │

Anseres, Anatidæ │ │ │ │ │

Struthiones, Rheidæ│ 1│ │ │ │

Total │ 6│ 9│ 2│ 2│ 4

───────────────────┴────────────────┴──────┴──────────┴──────┴─────

═══════════════════╤══════════════════════════════════════════╤════════════

Order Family │ │Notes Extra

│ │ cases not

│ │ tabulated.

───────────────────┼─────┬────────┬────┬──────┬───────┬───────┼────────────

„ „ │Ovary│Pancreas│Skin│Testes│Adrenal│Unknown│ „

│ │ │ │ │ │ │

───────────────────┼─────┼────────┼────┼──────┼───────┼───────┼────────────

Primates, │ │ │ │ │ │ │

Cercopithecidæ │ │ │ │ │ │ │

Cebidæ │ │ │ │ │ 1│ │Adenoma of

│ │ │ │ │ │ │ prostrate

│ │ │ │ │ │ │suggesting

│ │ │ │ │ │ │ cancer in

│ │ │ │ │ │ │ places.

Lemures, Lemuridæ │ │ │ │ │ │ │

│ │ │ │ │ │ │

Carnivora, Felidæ │ │ │ │ │ │ │Endothelioma

│ │ │ │ │ │ │ of pleura.

Viverridæ │ │ 1│ │ │ │ │

Canidæ │ │ 1│ │ │ │ │

Procyonidæ │ │ 1│ │ │ │ │

Ursidæ │ │ │ │ │ 1│ │Epithelioma

│ │ │ │ │ │ │ of tongue.

Phocidæ │ │ │ │ │ 1│ │

│ │ │ │ │ │ │

Rodentia, Sciuridæ │ │ │ │ │ │ │

Muridæ │ │ │ │ │ │ │

Heteromyidæ │ │ │ │ │ │ │Sarcoma of

│ │ │ │ │ │ │ bladder.

Octodontidæ │ │ │ │ │ │ │

Hystricidæ │ │ │ │ │ │ │

Dasyproctidæ │ │ │ │ │ │ │Squamous

│ │ │ │ │ │ │ carcinoma

│ │ │ │ │ │ │ of larynx.

Proboscidea │ │ │ │ │ │ │

Ungulata, Equidæ │ │ │ │ │ │ │

Bovidæ │ │ │ │ │ │ │

Cervidæ │ │ │ │ │ │ │

Camelidæ │ │ │ │ │ │ │

Suidæ │ │ │ │ │ │ │

Edentata, │ │ │ │ │ │ │

Dasypodidæ │ │ │ │ │ │ │

Marsupialia, │ │ │ │ │ │ │

Didelphyidæ │ │ │ │ │ │ │

Dasyuridæ │ │ │ 1│ │ │ │

Peramelidæ │ │ │ │ │ │ │

Macropodidæ │ │ │ │ │ │ │

Passeres, Turdidæ │ │ │ │ │ │ │

Crateropodidæ│ │ │ │ │ │ │

Tanagridæ │ │ │ │ │ │ 1│

Fringillidæ │ │ │ │ │ │ 1│

Icteridæ │ │ │ │ │ │ │

Striges, Bubonidæ │ │ │ │ │ │ │

Psittaci, Loridæ │ │ │ │ │ │ │

Cacatuidæ │ │ │ │ │ │ 2│

Psittacidæ │ 1│ │ │ 2│ 1│ 5│Glioma of

│ │ │ │ │ │ │ brain.

Accipitres, │ │ │ │ │ │ 1│

Falconidæ │ │ │ │ │ │ │

Columbæ, Columbidæ │ │ │ │ │ │ │

Galli, Phasianidæ │ 1│ │ │ │ │ │

Fulicariæ, Rallidæ │ │ │ │ │ │ │

Anseres, Anatidæ │ │ │ │ │ 1│ │

Struthiones, Rheidæ│ │ │ │ │ │ │

Total │ 2│ 3│ 1│ 2│ 5│ 10│

───────────────────┴─────┴────────┴────┴──────┴───────┴───────┴────────────

TABLE 22.

_Analytical Table Showing Data of Incidence, Sex, Breeding, Duration of

Captivity, Metastases and Embryological Origins and Distributions

According to Order._

════════════╤═══════╤═════╤════════╤═══════════════╤══════════╤═══════

Order │ Total │ Per │ Sex │ Breeding │ Range │Average

│animals│cent.│ │ │ known │ for

│ │ per │ │ │captivity │ tumor

│ │order│ │ │ │animals

────────────┼───────┼─────┼──┬──┬──┼────┬───────┬──┼──────────┼───────

„ │ „ │ „ │♂ │♀ │? │Wild│Captive│? │ „ │ „

────────────┼───────┼─────┼──┼──┼──┼────┼───────┼──┼──────────┼───────

Primates │ 2│ .4│ 2│ │ │ 2│ │ │3–4 yrs. │3½ yrs.

Lemures │ 1│ 1.1│ 1│ │ │ 1│ │ │4 yrs. │

Carnivora │ 17│ 3.5│ 8│ 9│ │ 14│ 3│ │1–18 yrs. │9 yrs.

Rodentia │ 12│ 6.│ 7│ 4│ 1│ 8│ 2│ 2│1 mo.–7 │2 yrs.

│ │ │ │ │ │ │ │ │yrs. │8 mo.

Insectivora │ 0│ │ │ │ │ │ │ │ │

Chiroptera │ 0│ │ │ │ │ │ │ │ │

Proboscidea │ 1│_33._│ │ 1│ │ 1│ │ │38 yrs. │

Hyracoidea │ 0│ │ │ │ │ │ │ │ │

Ungulata │ 7│ 1.9│ 2│ 5│ │ 5│ 1│ 1│2–16 yrs. │9 yrs.

Edentata │ 1│_6.2_│ │ 1│ │ 1│ │ │10 yrs. │

Marsupialia │ 7│ 4.│ 6│ 1│ │ 6│ 1│ │1 wk.–12 │5 yrs.

│ │ │ │ │ │ │ │ │yrs. │6 mo.

Monotremata │ 0│ │ │ │ │ │ │ │ │

Totals │ 48│ 2.58│26│21│ 1│ 38│ 7│ 3│ │

│ │ │ │ │ │ │ │ │ │

Passeres │ 7│ .51│ 4│ 2│ 1│ 6│ │ 1│1–14 yrs. │6 yrs.

Picariæ │ 0│ │ │ │ │ │ │ │ │

Striges │ 1│ .75│ │ 1│ │ 1│ │ │7 yrs. │

Psittaci │ 26│ 3.7│ 9│ 8│ 9│ 8?│ 16?│2?│5 mo.–9 │3 yrs.

│ │ │ │ │ │ │ │ │yrs. │

Accipitres │ 2│ 1.│ 2│ │ │ 2│ │ │(1)[93]–4 │

│ │ │ │ │ │ │ │ │yrs. │

Columbæ │ 1│ .63│ │ 1│ │ 1│ │ │4 yrs. │

Galli │ 1│ .33│ │ 1│ │ 1│ │ │? │

Hemipodii │ 0│ │ │ │ │ │ │ │ │

Fulicariæ │ 1│_2.8_│ 1│ │ │ 1│ │ │6 yrs. │

Alectorides │ 0│ │ │ │ │ │ │ │ │

Limicolæ │ 0│ │ │ │ │ │ │ │ │

Gaviæ │ 0│ │ │ │ │ │ │ │ │

Impennes │ 0│ │ │ │ │ │ │ │ │

Steganopodes│ 0│ │ │ │ │ │ │ │ │

Herodiones │ 0│ │ │ │ │ │ │ │ │

Odontoglossæ│ 0│ │ │ │ │ │ │ │ │

Palamedes │ 0│ │ │ │ │ │ │ │ │

Anseres │ 4│ 1.2│ │ 3│ 1│ 3?│ 1│ │(1)[93]-10│

│ │ │ │ │ │ │ │ │yrs. │

│ │ │ │ │ │ │ │ │(1)[93]-4 │

│ │ │ │ │ │ │ │ │yrs. │

Struthiones │ 1│_3.1_│ 1│ │ │ 1│ │ │(1)[93]-5 │

│ │ │ │ │ │ │ │ │yrs. │

Crypturi │ 0│ │ │ │ │ │ │ │ │

Totals │ 44│ 1.23│17│16│11│ 24│ 17│ 3│ │

Grand Totals│ 92│ 1.7│43│37│12│ 62│ 24│ 6│ │

────────────┴───────┴─────┴──┴──┴──┴────┴───────┴──┴──────────┴───────

════════════╤══════════════╤════════════════════════════════════

Order │Embryological │ Metastases

│ layer │

│ │

────────────┼────┬────┬────┼────┬─────┬──────┬───────────┬──────

„ │Ecto│Meso│Ento│Lung│Liver│Kidney│Lymphocytes│Spleen

────────────┼────┼────┼────┼────┼─────┼──────┼───────────┼──────

Primates │ │ 1│ 1│ │ │ │ │

Lemures │ │ │ 1│ │ │ │ │

Carnivora │ 2│ 8│ 7│ 5│ 1│ │ 1│

Rodentia │ 2│ 7│ 3│ │ │ │ │

│ │ │ │ │ │ │ │

Insectivora │ │ │ │ │ │ │ │

Chiroptera │ │ │ │ │ │ │ │

Proboscidea │ │ 1│ │ │ │ │ │

Hyracoidea │ │ │ │ │ │ │ │

Ungulata │ │ 5│ 2│ │ 1│ 1│ 1│

Edentata │ │ 1│ │ │ │ │ │

Marsupialia │ 2│ 2│ 3│ 1│ 2│ 1│ 1│ 2

│ │ │ │ │ │ │ │

Monotremata │ │ │ │ │ │ │ │

────────────┼────┼────┼────┼────┼─────┼──────┼───────────┼──────

Totals │ 6│ 25│ 17│ 6│ 4│ 2│ 3│ 2

│ │ │ │ │ │ │ │

Passeres │ │ 7│ │ 1│ 1│ │ │

Picariæ │ │ │ │ │ │ │ │

Striges │ │ │ 1│ │ │ │ │

Psittaci │ 1│ 17│ 8│ │ 2│ │ │ 1

│ │ │ │ │ │ │ │

Accipitres │ │ 2│ │ │ │ │ │

│ │ │ │ │ │ │ │

Columbæ │ │ 1│ │ │ │ │ │

Galli │ │ 1│ │ │ │ │ │

Hemipodii │ │ │ │ │ │ │ │

Fulicariæ │ │ 1│ │ │ │ │ │

Alectorides │ │ │ │ │ │ │ │

Limicolæ │ │ │ │ │ │ │ │

Gaviæ │ │ │ │ │ │ │ │

Impennes │ │ │ │ │ │ │ │

Steganopodes│ │ │ │ │ │ │ │

Herodiones │ │ │ │ │ │ │ │

Odontoglossæ│ │ │ │ │ │ │ │

Palamedes │ │ │ │ │ │ │ │

Anseres │ │ 4│ │ │ │ │ │

│ │ │ │ │ │ │ │

Struthiones │ │ │ 1│ │ │ │ │

│ │ │ │ │ │ │ │

Crypturi │ │ │ │ │ │ │ │

────────────┼────┼────┼────┼────┼─────┼──────┼───────────┼──────

Totals │ 1│ 33│ 10│ 1│ 3│ │ │ 1

────────────┼────┼────┼────┼────┼─────┼──────┼───────────┼──────

Grand Totals│ 7│ 58│ 27│ 7│ 7│ 2│ 3│ 3

────────────┴────┴────┴────┴────┴─────┴──────┴───────────┴──────

════════════╤═════════════════════╤══════════════

Order │ Metastases │Embryological

│ │ layer of

│ │ metastases

│ │

────────────┼─────────┬────┬──────┼────┬────┬────

„ │Intestine│Bone│Muscle│Ecto│Meso│Ento

────────────┼─────────┼────┼──────┼────┼────┼────

Primates │ │ │ │ │ │

Lemures │ │ │ │ │ │

Carnivora │ │ │ 1│ │ 5│ 5

Rodentia │ │ │ │ │ │

│ │ │ │ │ │

Insectivora │ │ │ │ │ │

Chiroptera │ │ │ │ │ │

Proboscidea │ │ │ │ │ │

Hyracoidea │ │ │ │ │ │

Ungulata │ │ │ │ │ 1│ 1

Edentata │ │ │ │ │ │

Marsupialia │ │ 1│ │ │ 2│ 3

│ │ │ │ │ │

Monotremata │ │ │ │ │ │

────────────┼─────────┼────┼──────┼────┼────┼────

Totals │ │ 1│ 1│ │ 8│ 9

│ │ │ │ │ │

Passeres │ 1│ │ │ │ 1│ 2

Picariæ │ │ │ │ │ │

Striges │ │ │ │ │ │

Psittaci │ 1│ │ │ │ 1│ 3

│ │ │ │ │ │

Accipitres │ │ │ │ │ │

│ │ │ │ │ │

Columbæ │ │ 1│ │ │ 1│

Galli │ │ │ │ │ │

Hemipodii │ │ │ │ │ │

Fulicariæ │ │ │ │ │ │

Alectorides │ │ │ │ │ │

Limicolæ │ │ │ │ │ │

Gaviæ │ │ │ │ │ │

Impennes │ │ │ │ │ │

Steganopodes│ │ │ │ │ │

Herodiones │ │ │ │ │ │

Odontoglossæ│ │ │ │ │ │

Palamedes │ │ │ │ │ │

Anseres │ │ │ │ │ │

│ │ │ │ │ │

Struthiones │ │ │ │ │ │

│ │ │ │ │ │

Crypturi │ │ │ │ │ │

────────────┼─────────┼────┼──────┼────┼────┼────

Totals │ 2│ 1│ │ │ 3│ 5

────────────┼─────────┼────┼──────┼────┼────┼────

Grand Totals│ 2│ 2│ 1│ │ 11│ 14

────────────┴─────────┴────┴──────┴────┴────┴────

For meaning of italics see foot note Table 1.

INCIDENCE OF TUMORS.

Examination of the table, (21) from the standpoint of differential

percentage reveals that mammals have 48 tumors giving an incidence of

2.58 per cent. whereas birds have 44 new growths equivalent to 1.23 per

cent. Were it not for the high figures for one single variety of bird

(Undulated Grass Parrakeet) this value for Aves would be still lower. At

all events our figures would indicate that the mammal is at least twice

as productive of neoplasms as is the bird. In our material the latter

class has had a better chance than Mammalia to show its susceptibility

since there have been nearly twice as many autopsies.

Within the classes the comparative figures have less value because of

the smaller and varying numbers. Such high percentages as are shown by

the elephants and armadillos cannot be taken as indicators for their

orders since too few specimens were examined. Judging by orders with

more than one hundred autopsies the rodents stand at the head of the

list followed by the marsupials and carnivores. It is interesting that

the animal nearest to man, the monkey, and with greatest number of

autopsies in its zoological class, has the lowest tumor incidence.

Psittaci lead the avian orders, followed by the Fulicariæ, but as there

are but thirty-five autopsies upon these, the second place rightly

belongs to the Anseres. All the principal orders are represented but the

only one of importance is the leader. The Psittaci are very prone to

have tumors in the renal area, sometimes of the kidney, at others of the

adrenal and occasionally of the sex glands. Some remarks have already

been given to this matter in the sections devoted to the kidney and

genitalia but it will be discussed again under tumor morphology.

Among these ninety-two animals, one bore multiple tumors, a Jaguar

(_Felis onca_) with adenomata of the liver and uterus and angiomata of

the mesentery. Careful study failed to reveal any parasitism as the

cause of the growths and since the first two were of slightly varying

structure it is not believed that one is a metastasis from the other.

The sex incidence stands in direct relation to the proportion of total

males and females posted or in other words it is the same for the two.

The figures might be somewhat affected were the gender of all the

parrakeets available but the tumors growing in the upper renal area

frequently destroy the sex gland.

Definite statements concerning the importance of breeding in the

causation of neoplasms cannot be made since we cannot quote figures for

the percentages of wild- and captive-born of our entire autopsy list.

The data are confused by scanty information concerning the twenty-six

parrots, the history of which is vague and I am perhaps too severe in

accrediting the birth of sixteen of them to captivity. This was done

because of a lack of exact information concerning these specimens and,

because their variety is known to breed when captive by the residents of

their habitat[94], the distribution into wild- and captive-born is based

upon what information we have. If the order Psittaci be subtracted

entirely, it leaves a total of 62 tumor-bearing animals of known

breeding, 49 of which were born in the wild, thirteen in captivity, a

fact which strengthens the thought that unnatural breeding increases the

chance of neoplasms.

The known length of captivity has also a direct bearing on this point.

The figures given in the columns “known captivity” and “average for

tumor bearers” were compared with figures obtained by averaging the

lives of fifty others (when possible) of the same order or of at least

three times as many as bore tumors. Animals dying from injury were

excluded. With one exception the average for “tumor bearers” exceeded

that for “non-tumor bearers”; the exception, the Ungulata, had the same

average for both groups. It seems then that tumors occur in animals in

captivity longer than the average for their order, or in specimens that

have the power to live under confined conditions until neoplasms

develop. In this respect I recall the statements made by Harlow

Brooks[95] that tumors will probably be found more commonly in animals

when they live in a manner comparable to that of urban man and that

racial degeneracy will favor their development. There is adduced here

perhaps the first definite evidence that long captivity allows tumor

tendency to express itself but it does not prove that confinement

increases tumors. Nor does the expectation of life, average or

potential, stand in any direct and definite relationship to the

frequency of neoplasms. The only clear case of long life and high tumor

incidence is to be found in Parrots; we feel however that some unknown

factor increases tumors of the renal-adrenal region in these birds and

that unqualified statements about age and tumor growth are not

permissible. Since tumors grow in many wild-born specimens, a high

percentage of which become known in the first few years of captivity, is

it not highly probable that tumors are reasonably common in the wild and

that we do not observe enough purely natural specimens to assume an

immunity on the part of free living beasts.

One of the undesirable features of captive breeding is consanguinity of

parents and there is good reason to believe that tumor susceptibility

can be bred into or out of a line of animals by mating tumor bearers and

non-tumor bearers, the tendency following the rules of Mendelian

inheritance (Slye). Is there any proof that inbreeding does not occur in

the wild and if it do, it is perfectly possible that tumor tendency may

be transmitted as a dominant character; the effect of artificial or

intentional inbreeding in captivity would only offer an opportunity for

a summation of these influences.

If injury and animal parasitism have any importance in neoplasmata then

this opportunity certainly occurs under natural conditions. Fibiger

observed gastric tumors in rats arising under the influence of nematodes

while Slye and Wells report facial neoplasms in mice apparently arising

at points of old injuries. It seems to me that we have no right to

assume an immunity of wild animals, in their native environment, to

tumors; the incidence is another matter but it may be considerable.

It was thought possible that there might be some light shed upon the

matter by an analysis of our sarcomatous and epitheliomatous tumors in

wild- and captive-born animals. In our second paper[96] upon this

subject I ventured the statement that sarcomatous growths occurred more

frequently in captive-born, epitheliomatous in wild-born specimens.

Greater data have not borne out this conclusion and information was

sought as to the embryonal derivation of tumor-bearing tissue. Analyzing

the cases in which all the factors could be obtained, it seems that

among seven tumors of captive-bred animals, five came from the entoderm,

two from the mesoderm, whereas in wild-bred animals, of the fifty-seven

tumors, five came from the ectoderm, thirty-two from the mesoderm and

fourteen from the entoderm. These figures do not include the parrots.

The sex values have no significance.

It is interesting and noteworthy, that, as in the human being, the

majority of the tumors came from tissues arising in the mesoderm and

that the entodermic derivatives received the largest number of

metastases; no ectodermic tissues were sites of secondary tumors. The

visceral seats of metastases are probably of little value for comparison

in so small a number; the lung and liver however occupy the prominent

places.

Interesting as the foregoing facts may be, they do not shed light upon

the question of breeding and degeneracy in the causation of neoplasms.

Attention is arrested however by the paucity of tumors in derivatives of

the ectoderm since in man new growths are common in the breast, at the

rectal and labial mucocutaneous junctions and on the skin. The immunity

of the ectodermic tissues to secondary growths is very distinct; this

holds true in man.

SPECIAL TUMORS.

The diagnosis of fibroma offers the same difficulty in the zoological

material as it does in man and even more care must be exercised for

solid tumors in certain localities. The bird often presents hard nodular

masses on the palmar and lateral aspects of the feet, sometimes

surmounted by callosities, to which the term fibroma or fibromatous

corns might be applied. Section of some of these will reveal areas of

granulation tissue about points of inflammation so that we have

considered them as infectious or the result of incorrect perches and

excluded them from the tumors. True fibromata have been encountered

thrice but in combination with muscle tissue as a fibromyoma thrice in

addition. The “fibroids” seen in the elephants and armadillo have

already been described.

The nodular growth sometimes accompanying degenerative disease of the

osseous system followed by attempts at repair as discussed under

osteitis deformans, leontiasis ossium and actinomycosis, are often

productive of masses to which it is easy to apply the term osteoma. If

one demand that an osteoma shall be a distinct neoplastic, localized

bony growth of unnatural or greatly exaggerated structure, then the

tumor is quite rare. We have seen one growing from the vertebræ and

clavicle of a gerbille and a fibro-osteoma on one jaw of an Isabelline

gazelle. The chondromata have been limited to one case, a unilateral

mass growing from the nasal cartilage of a caracal.

Lipomata are localized collections of fat consisting of cells with

greater fat capacity than normally, sometimes surrounded by an

indefinite capsule. Judging by the observations of Joest and Johne they

are reasonably common in horses and cows. We have not seen a single case

in mammals but eight cases appeared in the birds. These were with one

exception disposed under the skin mostly over the abdomen and chest and

once under the scalp. In a hawk the tumor grew as a pelvic mass

surrounding the cloaca and apparently caused decided obstruction to the

lumen. The lipomata of the Psittaci usually grow as pendulous masses on

the abdominal wall covered by thin, featherless, delicate skin, often

showing dilated veins. Upon section they are rather rich in blood

supply, “angiolipoma,” but fail to show any angiomatous or solid

cellular areas under the microscope. The frequency of the growths in one

variety (Roseate cockatoo—_Cacatua roseicapilla_) led to an attempt to

transplant the tumor. The plant seemed to thrive in the recipient for a

while but soon disappeared. Breeding experiments on the tumor bearers

are now under way.

Angiomata of lymph channels were observed in the omentum and mesentery

of a jaguar (_Felis onca_); this is the animal with three apparently

separate and distinct tumors. “The omentum is normally fatty and

slightly congested. In its meshes are myriads of tiny cysts containing

gray fluid. The main peritoneal area is negative but in the pelvic

region on anterior rectal wall, in the superior edge of the broad

ligament and in Douglas’ pouch, are cysts from a few millimetres to

several centimetres, with clear contents. The microscopic section of

omentum shows the multiple cysts as cavities of varying size, from that

of an arteriole to the diameter of a two-third lens field. They are

lined with flat, closely placed pavement cells with well stained but

vesicular nucleus. The septa are adult connective tissue. No contents or

granular eosin-staining material. No swollen cells like in adenomata. No

parasites seen.”

Two endotheliomata have been found, one of the flat variety with warty

excrescences common on serous surfaces, located in the pleura of a

leopard (_Felis nebulosa_), and one of the nodular variety, growing from

the clavicle of a Moorhen (_Gallinula chloropus_).

The sarcomata present their usual morphology grossly and minutely and

with the exception of the cases arising from the pectoral muscle and

from the genital area offer little of interest. Two instances in the

former location, observed in parrakeets, presented several puzzling

features. The component cells were spindle in shape, similar to a muscle

cell but were fitted with the round or elliptical nuclei of embryonal

cells. In a few places they were exceedingly large and had shadowy

outlines like a syncytium or they would be so arranged as to suggest a

glandular structure. The dominant type of cell was, however, everywhere

the spindle as it is seen in sarcoma. The sarcomata when they occur in

the genital area usually assume the alveolar arrangement and are of the

round or mixed cell variety. Only three of the sixteen sarcomata gave

metastases.

Papillomata of minor character appear occasionally on the skin of

animals as warts, but only one instance of any greater importance has

been found. The duodenal mucosa of an owl (_Bubo virginianus_) presented

a soft growth which partly obstructed the intestinal lumen. Papillary

adenomata, on the other hand, have been observed several times, but

since they have more importance as irregular hyperplasias of glandular

origin have been included in the next group. An interesting case was

seen in a baboon (_Papio hamadryas_) in which a large part of the

gastric wall was the seat of adenomata, presenting in addition several

distinct papillary outgrowths. A similar picture was found in the

duodenum of the rhea (_Rhea americana_).

The greatest interest in the adenomata centres around these growths in

the renal area in parrakeets, and as they have much in common with all

the glandular tumors of this region, a general discussion of this

subject may be introduced here. We have observed seven tumors

constructed on a glandular basis of renal or adrenal character. Grossly

these tumors develop as irregular masses usually of distinct brown

color, constructed on a lobular plan, delicate barely visible septa

dividing the growth. They seem devoid of large vessels, a gross

observation confirmed microscopically. There is no criterion to the

naked eye, which will distinguish the variety of epithelial hyperplasia

or permit separation of these neoplasms from some sarcomata; the latter

are usually gray but need not be so. Minutely studied, three of these

tumors proved to be adenomata, all papillary, one cystic as well. Three

had to be denominated carcinoma because of their distinct separate

crowded nests and incomplete acini. The cells comprising these growths

are comparable to the lining elements of the collecting tubules of the

renal lobule in that they have relatively large nuclei and a tendency to

basic staining protoplasm. The adenomatous picture is, however, more

comparable to the cortex than to the medulla. The remaining tumor was a

hypernephroma of the usual large cell, acinus-forming type and seemed to

originate in the adrenal. None of these tumors in the parrakeets sent

out metastases. Other hypernephromata have been diagnosed, to the number

of six. Upon review of their descriptions and sections, the

determinations are to be confirmed. However, it must be recorded here

that none of the three in mammals gave metastases, while two of the

three in birds did so. They are all of the usual type with large

vacuolated cells in glandular groups or strands.

Three rather interesting examples of epithelioma have been observed. The

first and most important was a basocellular growth of the tongue in a

black bear (_Ursus americanus_). The local damage—ulceration and

infiltration—and swelling sufficient to interfere with deglutition, were

quite considerable. The basal cell nests had penetrated deeply into the

muscle, but extension had taken place only to a single submaxillary

gland. A squamous epithelioma was found on the skin of the thigh of a

Tasmanian devil (_Sarcophilus ursinus_). The construction was somewhat

unusual in that it was cystic but lined with squamous and keratinized

plates. It could not be decided that it originated from glands like a

trichoepithelioma; it was not like a basal cell cancer. No metastases

had occurred. The third case was that of a tumor within the abdomen of

an Amazon (_Chrysotis leucocephala_). It consisted of an illy defined

basement membrane upon which were irregular stratified squamous

epithelial cells. Upon the surface were wavy bands of horny material,

very much like dried and cast-off epithelial scales, except more compact

and extensive. These latter seemed to form the bulk of the mass. Beneath

the membrane a few irregular accumulations of cells bearing a similarity

to those on the surface could be found, but they were probably large

plasma cells. The epithelial layer dipped down like in epithelioma. No

pearls or separate nests were found. While this mass was not localized,

it was doubtless an epithelioma, and should be included in this series.

Its possible origin in the small intestine has been considered.

The question of the occurrence of tumors in wild animals seems fairly

well settled when twenty-five examples of malignant epithelial neoplasms

can be discovered in fifty-three hundred autopsies. It is interesting to

note the incidence of these tumors in wild- and park-bred animals.

Exclusive of the parrakeets there are twenty-one cancers, seventeen in

known wild-bred, two in known park-bred specimens, and two with breeding

uncertain. The average known duration of captivity of the wild-bred

animals is about four years, while the two park-bred animals lived eight

and eighteen years. Thirteen of the twenty-one cases were males, eight

females. Adenocarcinoma was discovered twelve times, simplex nine times,

medullary and squamous each twice. Three tumors of the pancreas and

mammary gland were seen in which fibrotic or scirrhus areas were found,

but in no case was there detected that hard cicatrizing cancer so

commonly found in the human breast. All the interesting cases of

carcinoma have been recorded in the discussion of organs from which they

took origin. The only case of chorionepithelioma has been reported in

detail on page 308. The two cases of mixed tumors are as follows: Mixed

tumor of the thyroid and adenocarcinoma sarcomatodes in the liver; they

have been discussed in detail on pages 334 and 242 respectively.

[Illustration:

FIG. 49.—BASAL CELL CARCINOMA OF TONGUE. BLACK BEAR (URSUS

AMERICANUS). NOTE ULCERATION WHERE PIECE HAS BEEN EXCISED, AND ALSO

NODULAR THICKENING OF WHOLE BASE OF TONGUE.

]

[Illustration:

FIG. 50.—MICROSCOPICAL APPEARANCE OF TUMOR IN FIG. 49.

]

Analysis of the incidence of tumors according to organs is disturbed by

the large number of cases in Psittaci. Including this order the first

place is taken by the kidney, followed by the liver, uterus, muscle,

gastrointestinal tract, bone and cartilage, thyroid, adrenal and lung in

this order. Curiously enough, if these birds be subtracted the degree of

organ susceptibility to new growths is not greatly altered. The lead is

still held by the kidney, the uterus occupying the second place and then

in sequence the liver, gastrointestinal tract, muscle, thyroid and

adrenal. Examination of the figures for mammals shows the uterus to lead

in numbers, followed by the liver, thyroid, and mammary gland. For the

birds the kidney takes the undisputed head of the column with a total of

twelve tumors (27 per cent. of all avian tumors); the next figures are

shown by the liver, gastrointestinal tract and muscle.

ZOOLOGICAL AND PATHOLOGICAL LIST OF TUMORS

MAMMALIA

PRIMATES (2)

Cercopithecidæ—Hamadryas Baboon (_Papio hamadryas_)

Papillary adenoma of gastric mucosa

Cebidæ—Brown Cebus (_Cebus fatuellus_)

Hypernephroma of right adrenal

LEMURES (1)

Lemuridæ—Ring tailed Lemur (_Lemur catta_)

Papillary adenoma of prostate

CARNIVORA (17)

Felidæ—Clouded Leopard (_Felis nebulosa_)

Endothelioma of pleura

Caracal (_Felis caracal_)

Osteochondroma of nose

Lion (_Felis leo_)

Malignant adenoma of cervix uteri

Metastases to lung

Jaguar (_Felis onca_)

Fibroadenoma of uterus

Fibroadenoma of bile ducts

Lymphangioma of mesentery

Viverridæ—Indian Paradoxure (_Paradoxurus niger_)

Adenocarcinoma of pancreas

Malayan Civet (_Viverra tangalunga_)

Carcinoma of lung

Canidæ—Corsac Fox (_Canis corsac_)

Adenoma of pancreatic ducts

Red Fox (_Canis vulpes pennsylvanicus_)

Cystic adenoma of bile ducts

Raccoon-like Dog (_Canis procyonoides_)

Adenocarcinoma sarcomatodes of thyroid

Gray Fox (_Canis cinereo argenteus_)

Papillary cyst adenoma of bile ducts

Prairie Wolf (_Canis latrans_)

Sarcoma of thyroid region

Metastases to lungs

Prairie Wolf (_Canis latrans_)

Sarcoma of thyroid region

Procyonidæ—Common Raccoon (_Procyon lotor_)

Adenoma of pancreas

Ursidæ—Polar Bear (_Ursus maritimus_)

Adenocarcinoma of adrenals

Metastases to lungs, lymph nodes, diaphragm

Black Bear (_Ursus americanus_)

Medullary carcinoma of breast

Metastases to lungs

Black Bear (_Ursus americanus_)

Epithelioma of tongue

Phocidæ—California Hair Seal (_Zalophus californianus_)

Hypernephroma of adrenal

RODENTIA (12)

Sciuridæ—Beechy’s Spermophile (_Citellus grammurus beecheyi_)

Osteoma of sternum

Gray Squirrel (_Sciurus carolinensis pennsylvanicus_)

Hypernephroma of kidney

Woodchuck (_Arctomys monax_)

Adenoma simplex of liver

Muridæ—Waltzing Mouse (_Mus wagneri rotans_)

Adenocarcinoma of thigh muscles

White footed Mouse (_Peromyscus leucopus_)

Carcinoma simplex of mammary gland

White footed Mouse (_Peromyscus leucopus_)

Spindle celled sarcoma of leg

White footed Mouse (_Peromyscus leucopus_)

Carcinoma of mammary gland

Larger Egyptian Gerbille (_Gerbillus pyramidum_)

Fibrosarcoma of shoulder region

Heteromyidæ—Kangaroo Rat (_Perodipus richardsoni_)

Sarcoma of urinary bladder

Octodontidæ—Coypu Rat (_Myocastor coypus_)

Sarcoma of thyroid

Hystricidæ—Canada Porcupine (_Erethizon dorsatus_)

Chorionepithelioma uteri

Dasyproctidæ—Azara’s Agouti (_Dasyprocta azara_)

Squamous carcinoma of larynx

PROBOSCIDEA (1)

Indian Elephant (_Elephas indicus_)

Leiomyoma, uterine cornua and fimbria

UNGULATA (7)

Equidæ—Chapman’s Zebra (_Equus burchelli chapmani_)

Fibroma peritonei with sarcomatous and osseous

change and metastases to lung

Bovidæ—Isabelline Gazelle (_Gazella isabella_)

Osteofibroma of jaw with mucoid degeneration

Nylghaie (_Boselaphus tragocamelus_)

Fibroma uteri

Dorcas Goat (_Capra hircus_)

Lymphosarcoma of mediastinum with metastases

to liver, kidney and lymph nodes

Cervidæ—Common Deer (_Mazama virginiana_)

Fibroadenoma of bile ducts

Camelidæ—Alpaca (_Lama pacos_)

Carcinoma of liver or bile ducts with extension

to intestine

Suidæ—Wild Boar (_Sus scrofa_)

Carcinoma uteri

EDENTATA (1)

Dasypodidæ—Nine banded Armadillo (_Tatu novemcinctus_)

Fibroma uteri

MARSUPIALIA (7)

Didelphyidæ—Common Opossum (_Didelphys virginiana_)

Adenoma of kidney

Common Opossum (_Didelphys virginiana_)

Adenocarcinoma of mammary gland

Dasyuridæ—Spotted tailed Dasyure (_Dasyurus maculatus_)

Adenocarcinoma of intestines with metastases to

lymphatics, liver, spleen, lungs

Tasmanian Devil (_Sarcophilus ursinus_)

Cystic epithelioma of skin of thigh

Peramelidæ—Rabbit eared Bandicoot (_Thylacomys lagotis_)

Carcinoma of lung

Macropodidæ—Red Kangaroo (_Macropus rufus_)

Malignant papilloma of stomach

Metastases to liver, spleen, kidney

Red Kangaroo (_Macropus rufus_)

Carcinoma of lung

Metastases to spleen and gastric wall

AVES

PASSERES (7)

Turdidæ—American Robin (_Planesticus migratorius_)

Hypernephroma of kidney, metastases to intestine

Crateropodidæ—Jungle Babbler (_Crateropus canorus_)

Adenoma of kidney

Tanagridæ—Palm Tanager (_Tanagra palmarum_)

Lipoma of abdominal wall

Fringillidæ—Saffron Finch (_Sycalis flaveola_)

Adenocarcinoma of kidney

Chestnut-eared Finch (_Amadina castanotis_)

Adenocarcinoma of kidney with metastases to lung

Chestnut headed Bunting (_Emberiza luteola_)

Lipoma of scalp

Icteridæ—European Blackbird (_Merula merula_)

Hypernephroma of kidney region with metastases to liver

STRIGES (1)

Bubonidæ—Great Horned Owl (_Bubo virginianus_)

Papilloma of duodenum

PSITTACI (26)

Loriidæ—Musky Lorrikeet (_Glossopsittacus concinnus_)

Carcinoma of lung

Cacatuidæ—Roseate Cockatoo (_Cacatua roseicapilla_)

Lipoma of abdominal wall

Roseate Cockatoo (_Cacatus roseicapilla_)

Multiple lipomata of abdominal wall

Psittacidæ—Undulated Grass Parrakeet (_Melopsittacus undulatus_)

Glioma of brain with metastases to liver