secūrī, sitī, tussī, vī, _axe_, _thirst_, _cough_, _strength_
canālī, cucumī, _conduit_, _cucumber_
Some names of rivers and cities have only #-ī#: as, #Tiberī#, #Hispalī#.
The locative also ends in #-ī#: as, #Neāpolī#, _at Neapolis_.
555. (_b._) These ablatives of gender substantives with the nominative
in #-is# have #-ī# or #-e#:
amne, -ī, _river_
ave, -ī, _bird_
bīle, -ī, _bile_
cīvī, -e, _citizen_
classe, -ī, _fleet_
clāvī, -e, _key_
febrī, -e, _fever_
fūstī, -e, _club_
ignī, -e, _fire_
nāvī, -e, _ship_
orbī, -e, _circle_
puppī, -e, _stern_
sēmentī, -e, _planting_
strigilī, -e, _skin-scraper_
turrī, -e, _tower_
556. A few other words in #-is# have occasionally an ablative in #-ī#:
as, #anguis#, _snake_, #collis#, _hill_, #fīnis#, _end_, #postis#,
_post_, #unguis#, _nail_, &c. #sors#, _lot_, #imber#, _shower_, and
#lūx#, _light_, have also #-e# or #-ī#; #supellēx#, _furniture_, has
#supellēctilī# or #-e#; #Arar# has #-e# or #-ī#; #Liger#, #-ī# or #-e#.
557. Neuter names of towns with the nominative in #-e# have #-e# in the
ablative: as, #Praeneste#. #rēte#, _net_, has only #rēte#; #mare#,
_sea_, has rarely #mare# (527).
558. (2.) Adjectives ‘of two endings’ with stems in #-i-# (630) often
have #-e# in the ablative when they are used as substantives, and
sometimes in verse, when a short vowel is needed: as,
#adfīnī#, #-e#, _connection by marriage_; #aedīle#, #-ī#, _aedile_;
#familiārī#, #-e#, _friend_. But some, even as substantives, have #-ī#:
as, #aequālī#, _of the same age_, #cōnsulārī#, _ex-consul_, #gentīlī#,
_tribesman_. Adjectives of place in #-ēnsis# (330) usually have #-ī#,
but sometimes #-e#: as, #Tarquiniēnse#. Proper names have usually #-e#:
as, #Iuvenāle#.
559. Adjectives ‘of one ending’ with stems in #-i-# (632), have commonly
#-ī# in the ablative. The following ablatives have only #-ī#:
#āmentī#, _frenzied_, #ancipitī#, _two-headed_, #praecipitī#,
_head-first_, #concolōrī#, _of like hue_, #concordī#, _harmonious_,
#discordī#, _at variance_, #sōcordī#, _imperceptive_, #dēgenerī#,
_degenerate_, #dītī#, _rich_, #teretī#, _rounded_, #ingentī#, _huge_,
#inopī#, _without means_, #memorī#, _remembering_, #immemorī#,
_forgetful_.
560. Present participles, when used as adjectives, have #-ī# in the
ablative, otherwise #-e#: as,
#ā sapientī virō#, _by a wise man_; #adulēscente#, _youth_, substantive;
#Rōmulō rēgnante#, _in the reign of Romulus_, ablative absolute (1362).
561. Other adjectives ‘of one ending’ occasionally have #-e# in the
ablative when used as substantives or as epithets of persons, or in
verse when a short syllable is needed: as,
#cōnsortī#, _sharing_, #parī#, _equal_, #vigilī#, _wide-awake_,
#fēlīcī#, _happy_, as adjectives; but #cōnsorte#, &c., as substantives;
in prose, #imparī#, #disparī#, _unequal_; in verse, #impare#, #dispare#.
Proper names have #-e#: as, #Fēlīce#.