96 CLASS XIV. 



Cyprinodon Lac. Head depressed; iiitermaxillaiy bone pro- 

 tractile. Teeth in maxillte small. Brancluostegous membrane with 

 five rays, more rarely six. Body compressed. 



a) Branchiostegous tnembrane with 5 rays. 



Pcecilia Bl., Yal. Teeth in maxillfe mobile, hiciirved, in a single 

 row; teeth crowded and very thin behind this row. 



Sp. Pcecilia surinamensis Valenc, Cuv. R. Ani., ed. ill., Poiss. PI. 95, fig. i ; 

 compare DuVEKNAY, see above, p. 42, &c. 



Mollienisia Lesueur. Sp. Mollienisia latipinna Les., Cuv. 1. 1. fig. 4 ; 

 this species from North America is distinguished by a very long dorsal fin 

 (of 14 rays) and by the position of the ventral fins close behind the 

 pectorals. 



Cyprinodon Lac, Lebias Cuv. Maxillary teeth in a single row, 

 tripartite at the apex. 



Sp. Cyprinodon calaritanus Val., Lebias calaritana Bonelli, &c. 



Fundulus Lac. Maxillary teeth very thin, crowded. 



Sp. Fundulus cosnicolus Val., Cohilis heteroclita L., Cuv. et Val. Poiss. 18, 

 PI. 580, &c. All the species of this sub-genus are from America. 



6) Branchiosterjous membrane with 6 7'ays. 



Hydrargyra Lac. {Cyprinodon Val. previously). Maxillary teeth 

 very thin, crowded. 



Sp. Hydrargyra swampina Lac. ; — Hydrarg. hispanica Val., Poiss. PI. 531, 

 fig. I. 



Orestias Valenc. Teeth in maxilla3 conical, thin, crowded. 

 Branchiostegous membrane with five rays. Dorsal fin remote, 

 opposite to anal. Ventral fins none. 



Sji. Orestias Cuvierii Valenc, 1. 1. PI. 352 ; from the lake Titicaca; the 

 largest species of the genus becoming 8 or 9 inches long. Most of the 

 other species of Orestias and Cyprinoden are under 3". The eyes are mostly 

 large. In small species of this and the preceding genus the cranial bones 

 are veiy thin, and so transparent that the brain is seen lying within the 

 cranium. 



Family XV. Characini. Body covered with scales distinct, 

 regular, imbricated. Dorsal fins mostly two, the posterior adipose. 

 Superior margin of mouth formed in the middle by the intermax- 

 illary bone, at the sides by the supramaxillaries. Rays of bran- 

 chiostegous membrane mostly four, more seldom five. Teeth 



