290 
ACTINOPTERYGII. 
mouth ; teeth on premaxilla and dentary, none on palate, except 
very rarely on vomer. Opercular apparatus complete, with fe' 
(4 to 6) branchiostegal rays and no gular plate. Abdonuuft^ 
vertebrae with transverse processes ; ribs stout and long, ltctora 
arch without precoracoid process. A singlo dorsal fin, more 
less remote, without adipose dorsal. Trunk covered with scu 
which extend more or less over the head. j. 
The existing Cyprinodonts are small fishes ranging throng ° 
the temperate and tropical regions, except Australasia, the raa ^ r oJ1 
confined to freshwaters, but a few found in brackish water an 
the sea-coast. 1 Only one extinct genus is known with certain . < 
while a second is recognised provisionally. 
4 
Genus PROLEBIAS, Sauvago. 
[Bull. Soc. Hist. Nat. Toulouse, vol. viii. 1874, p- 1^7.] ^ ^ 
Trunk regularly fusiform, laterally compressed ; caudal 1 )C ^^ 
deep. Head very small, with obtuse snout; cleft o ® ^ 
relatively small ; premaxilhc not produced forwards, and pro • ^ 
not protractile ; tooth simply conical, apparently arrange ^ 
singlo series. Transverse processes of abdominal vertebral ^ 
short. Pelvic fins present but relatively small; dorsal an 
fins small, not much extended, directly opposed in the bin 8T me _ 
of the fish ; anal fin never modified : caudal fin truncated or . S ^j on s 
what forkod. Scales large, ornamented with fine parallel stn 
and pectinations. The two sexes apparently similar. oX isfcing 
This genus seems to bo most closely related to the 
Lucania, Girard, of North America, and Funclulus, Lacepi °, ^ 
has a still more extensive range in North America besi es 
abundant in tropical Africa and southern Europe. 
Prolebias cephalotes (Agassiz). ^ 
1839. Lebias cephalotes , L. Agassiz, Poiss. Foss. vol. v. pt- 1 ^ 
pi. xli. figs. 1,2,9, 10. 
Bull. Soc. Hist. 
1874. Prolebias cephalotes, IT. E. Sauvage, 
Toulouse, vol. viii. p. 192. < . 
1891. Lebias cephalotes, C. Pollini, Sciamo Pesci foss. ricop 
Nat- 
Calc, marnoso, with photo. 
Type. Slab with numerous fishes ; olirn Murchison Colh^ 0 f 
The type species, attaining a length of about 0-035. ^ j c pth 
head with opercular apparatus about equal to tho maximu ^ 
1 S. Garman, “The Cyprinodonts,” Mem. Mus. Comp. Zool. Harvard 
vol. xix, no. 1 (1895). 
