"The maxillary palpi are obsolete. Fore-wings with vein 1b usually
furcate, but with lower fork often weak or tending to be obsolete, 5
rising not nearer to 4 than to 6, parallel, 7 and 8 out of 9. Hind-wings
almost always with frenulum, 1c absent. (Plate II., figs. 19 to 64, and
Plate I., figs. 12 and 13.)
"Imago with fore-wings more or less broad-triangular; hind-wings
broad-ovate."--(Meyrick.)
Larva (in New Zealand) generally with 10 or 12 legs only (Plate III.,
figs. 12, 17, 18, 19, 20, 21, 22, and 24), rarely with 16 (_Sphinx_, Pl.
III., figs. 13 and 14).
"Pupa with segments 9 to 11 free; not protruded from cocoon in
emergence."--(Meyrick.)
This is a very extensive group of the Lepidoptera, and so far as it is
represented in New Zealand is equivalent to that group formerly known as
the _Geometrina_, with the addition of the family _Sphingidæ_. The insects
here included comprise many of our most interesting, abundant, and
beautiful species. Some of them are so extremely variable that it is often
a matter of considerable difficulty to determine the most convenient points
on which to base the specific distinctions; although fortunately great
advances have been made in this direction of late years owing to the
increase in the number of workers, and the consequent accumulation of
available material. In connection with this portion of the subject, special
mention should be made of Mr. Meyrick's paper on the group, which appeared
in the 'Transactions' of the New Zealand Institute for 1883. This essay has
been of the greatest value in dispelling the doubts which formerly existed
respecting the limits of many of the most variable species.
The _Notodontina_ are represented in New Zealand by the six following
families:--
1. HYDRIOMENIDÆ. 4. ORTHOSTIXIDÆ.
2. STERRHIDÆ. 5. SELIDOSEMIDÆ.
3. MONOCTENIADÆ. 6. SPHINGIDÆ.
Family 1.--HYDRIOMENIDÆ.