124 VERTEBRATE ANIMALS OF THE UNITED STATES 



V. pellucidus (Baird). Sand darter (Fig. 60). Length 75 mm.; 

 head 4 to 4.75; depth 7 to 8.5; body translucent; nose very sharp; a series 

 of small spots along the back and another along each side; cheek and 

 opercle scaly; rays of dorsal fins X-io; anal I, 8 to 10; scales 67 to 78: 

 Lake Erie to Minnesota; southward to Kentucky and Texas; common 

 in clear, sandy streams. 



V. vivax (Hay) . A dusky bar across the base of the soft dorsal fin : 

 Mississippi to Arkansas and Texas. 



18. loa Jordan & Brayton. Similar to Vigil, but with 2 spines 

 in the anal fin: 2 species. 



/. vitrea (Cope). Length 50 mm.; head 4 to 4.5; depth 7 to 7.5; 

 color translucent, with small dark spots on the back and sides; rays of 

 dorsal fins VII to IX-ii to 14; anal II, 6 to 9; scales 50 to 62; belly 

 partly naked: eastern Virginia and North Carolina; common. 



19. Poecilichthys Agassiz. Body elongate and brightly colored; 

 belly with ordinary scales; gill membranes broadly joined across the 

 isthmus; premaxillaries not protractile; ventral tins well separated: 

 I species. 



F. variatus (Kirtland). Body moderately elongate; head short and 

 blunt and very rugose; length 100 mm.; head 3.5 to 4.4; depth 4.8 to 5.5; 

 color greenish; sides and belly orange, with 5 bands posteriorly; anterior 

 dorsal fin with a blue band; female paler; fins very large; rays of dorsal 

 fins XII to XIV-ii to 13; anal II, 7 to 9; scales 8-51 to 63-12: Ohio 

 basin to Arkansas; rare. 



20. Nanostoma Putnam. — Similar to Poecilichthys, but with a 

 small anal fin, much smaller than the soft part of the dorsal: 7 species. 



N . swannanoa (Jordan & Evermann). Body robust; length 75 mm. ; 

 head 4.3; depth 6; head naked, very short and blunt; color green, with 

 6 distinct dark cross blotches on the back and 8 or 10 on the sides; 

 cheeks, opercles and breast naked; rays of dorsal fins XI or XII- 12 to 

 14; anal II, 9; scales 6-48 to 57-7 or 8: upper waters of the Tennessee 

 River; common. 



iV.' thalassinum (Jordan & Brayton). Length 60 mm.; head 3.6; 

 depth 4.75 to 5; color dark green, blotches above and with 6 to 9 dark 

 vertical bars; dorsal fins reddish; females duller; head and throat naked; 

 rays of dorsal fins IX to XI-io to 12; anal II, 7 or 8; scales 5-40 to 48-7: 

 Santee River basin; very abundant. 



N. zonale (Cope) (Fig. 61). Body slender; length 75 mm.; head 4 or 

 5; depth 5 or 6; color olivaceous, with large dorsal spots which connect 

 with a lateral band from which 8 bands encircle the belly; rays of dorsal 

 fins X or XI-IO to 12; anal II, 6 to 8; scales 6-48 to 53-9; cheeks, 



