KEY TO THE PRINCIPAL SPECIES OF SNAKES AND 

 LEGLESS LIZARDS 



L Ventral scales small, not conspicuously different from the dorsal scales, 

 or apparently scaleless 2. 



Ventral scales larger than the dorsal scales and much lengthened 



crosswise 1 1 . 



2. With external ear openings; with a fold of skin lengthwise along each 



side; Va. to Wis., southward to Fla. and N. M. 

 Ophisaurus ventralis (Linn.) Glass Snake 

 (A legless lizard) 

 No external ear openings; no fold of skin along each side 3. 



3. Scales inconspicuous; body with external rings, appearing like an earth' 



worm; no visible eyes; Fla. 



Rhmeura fioridana (Baird) Florida Worm Li2;ard 

 (A legless lizard) 

 Body without external rings; with traces of eyes and with visible scales 4. 



4. Upper jaw pointed and not projecting much beyond the lower jaw; eyes 



as lengthwise slits; with about five large plates side by side in front of 

 anus; California (Legless lizards) 5. 



Upper jaw blunt and rounded and projecting much beyond the lower; 

 eyes round and covered with thin skin; with only one large transverse 

 plate before the anus; Family Leptotyphlopidae Blind Snakes 6. 



5. Back silvery or buff 



Anniella pulchra puchra Gray Silver California Worm Lizard 

 Back dark brown 



Anniella pidchra nigra Fischer Black California Worm Lizard 



6. With three small plates side by side on top of the head between the 



plates containing the eyes 7. 



With only one transverse plate on top of the head between the plates 



containing the eyes 8. 



7. With an undivided upper labial between the nasal and the descending 



plate (ocular) surrounding the eye; Okla. and Texas 



Leptotyphlops didcis didcis (B. & G.) Texas Blind Snake 

 (Glanconia dulcis (B. 5? G.) ) 

 With a divided upper labial so situated; Texas and Ariz, to Kansas 

 Leptotyphlops dulcis dissectus (Cope) Prairie Blind Snake 



8. With five light-colored rows of scales along the middle of the back; Cal. 



and Ariz. 



Leptotyphlops hurmlis cahuilae Klauber Desert Blind Snake 

 With seven dark-colored rows of scales along the middle of the back 9. 



9. With ten rows of scales on tail; Texas 



Leptotyphlops humilis segregus Klauber Mexican Blind Snake 

 With twelve rows of scales on tail 10. 



10. Mid-dorsal scale count less than 287; fifth mid-dorsal scale scarcely wider 

 than sixth; Cal., Nev. and Utah 



Leptotyphlops humdis humilis (B. &? G.) California Blind Snake 



391 



