Vol. IV] VAN DENBURGH AND SLEVIN— ISLAND REPTILES 



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necting the posterior surfaces of the thighs, in 34 specimens 

 from all the islands, varies from 55 to 61 ; being 55 three times, 

 56 four times, 57 five times, 58 eleven times, 59 five times, 

 60 five times, and 61 once. 



7. Hypsiglena ochrorhynchus Cope. 



A single specimen (No. 13602) collected February 22, 1908, 

 is labeled Coronado Islands. The scales are in 21 rows, 

 gastrosteges 178, anal divided, urosteges 44, supralabials 8-8, 

 infralabials 10-10, preoculars 2-2, postoculars 2-2, loreal 1-1, 

 temporals 1+2-1+2, genials equal. 



8. Pituophis catenifer (Blainville). 



Two specimens from South Coronado Island are at hand. 



No. 13588, April 6, 1908, has 31 scale rows, 231 gastro- 

 steges, 65 urosteges, supralabials 8-8, infraliabials 12-12, pre- 

 oculars 2-2, postoculars 3-3, loreal 1-1, anterior genials longer. 



No. 13589, April 11, 1908, has 35 scale rows, 229 gastro- 

 steges, 71 urosteges, supralabials 9-9, infralabials 13-13, pre- 

 oculars 2-2, postoculars, 3-3, loreal 1-1, temporals 3+3-3+3, 

 anterior genials longer. 



9. Crotalus oregonus Holbrook. 



We have seven rattlesnakes of this species from these islands. 

 Nos. 13583 to 13587 were collected on South Coronado, April 

 6-11, 1908. No. 13476 was secured on East Coronado, Feb- 

 ruary 15, 1908, No. 13603 is labeled merely Coronado Islands, 

 February 22, 1908. No. 13586 contains the remains of a 

 lizard {Eumeces) which it had eaten. Variation in scales is 

 shown in the following table: 



SCALE COUNTS IN CROTALUS OREGONUS. 



