1 66 VERTEBRATE ANIMALS OF THE UNITED STATES 



and the darker sides ; sides black ; 

 costal grooves 13-14. 



fi A definite stripe on side Eurycea gultolineata. 



{■2 No definite stripe on side Eurycea longicaiida. 



Eurycea melano pleura, 

 tz A sharp but broken demarcation 

 between the lighter back and the 

 darker sides. • 



fi Costal grooves 14-15 Eurycea hislineata. 



i-i Costal grooves 20 Eurycea multiplicata. 



d2 Digits on hind leg 4 Eurycea qnadridigitata. 



Suborder 3. Meantes. Three pairs of gills persistent throughout 

 life; maxillaries wanting; vomers wanting, vertebrae amphicoelous : i 

 family. 



Family i. Sirenidae. — Body very elongate, eel-shaped; hind legs 

 and pelvis wanting; carpus cartilaginous; 3 pairs of external gills which 

 atrophy in the young and grow again in the adult; i or 3 pairs of gill 

 slits; eyes very small; 2 patches of teeth on parasphenoid; premaxil- 

 laries and mandibles toothless and with horny sheaths: 2 genera and 

 species. 



Key to the Genera of Sirenidae 



El Leg with 4 toes i. Siren. 



a2 Leg with 3 toes 2. Pseudohranchus. 



1. Siren L. Four toes on each leg; 3 pairs of gill-slits present: i 

 species. 



S. lacertina L. Mud eel. Body dark gray above, lighter beneath, 

 more or less cylindrical in shape; head flattened; snout truncate; 

 tail compressed; lateral grooves 31 to 37; length 700 mm.; tail 240 mm.; 

 fore leg 38 mm.: south Atlantic and Gulf States, from District of 

 Columbia and central North Carolina to the Rio Grande, and north- 

 wards in the valley of the Mississippi to Alton, Illinois and Lafayette, 

 Indiana; in swamps; often common. 



2. Pseudobranchus Gray. Three toes on each leg; i pair of gill 

 slits: I species. 



P. striatus (LeConte). Body light with dark stripes; snout pointed; 

 mouth very small; length 150 mm.; tail 65 mm.; fore leg 4 mm.; gills 

 often covered by a fold of skin: South Carolina to Florida; in swamps; 

 not common. 



Order 2. Salientia (Anura). — Frogs and toads. Amphibians with 

 two pairs of well developed legs and without a tail in the adult stage, 

 but with a long tail and weak legs during some stage of the larval life 



