162 PROCEEDINGS OF THE ACADEMY OF [Mar., 



become very narrow and the elongate black borders constitute most 

 of the spots. The third row on the first four rows of scales only 

 shows distinctly in the anterior region. The venter has a tinge of 

 the color of the back, but appears to be mainly white or yellowish- 

 white, tessellated or checkered with quadrangular black spots. In 

 markings of the head these specimens very well agree with Elaphe 

 guttatus guttatus. 



Dimensions and Variations. — ^These two specimens are, respect- 

 ively, 97.3 and 111.8 cm. long; the tails, 16.2 and 18.7 cm., or 6 in 

 the total length; the gastrosteges are 218, 227; the urosteges, 69 

 and 68; anal divided; the scales are 24-27-18 and 23-27-19; the 

 oculars 1-2; the temporals 2-3 (4) and 2-3; the supralabials 8; 

 the infralabials 11 and 12.. 



Food. — This species belongs to the group known as rat snakes, 

 and each specimen proves true to racial reputation. In the stomach 

 of each we found a full-grown rice-field rat {Onjzoniijs palustris) and 

 other remains. Both of the rats had been swallowed head first, and 

 we firmly believe them to have been taken alive. This requires 

 considerable dexterity in nature where the prey is not cornered and 

 may also be another bit of evidence to show this species more aquatic 

 than usually thought. No parasites were found in the alimentary 

 tract of either specimens. 



7. Elaphe obsoletus (Say): Pilot Snake; Chicken Snake; Spotted Chicken Snake; Gray 

 Coluber; Gray Rat Snake. Fig. 9. 



Six specimens of this puzzling form were taken, and we regret 

 this series is not larger. However, this small collection confirms 

 us in the belief that Scotophis confinis B. and G., Coluber obsoletus 

 lemniscatus Cope, Coluber spiloides Dum and Bib., possibly Scotophis 

 latus B. and G., and Coluber quadrivittatus Holbrook are individual 

 variations of Elaphe obsoletus. This conclusion in its main features 

 is in agreement with Boulenger and Rhoades and partly in accord 

 with Hay's and Brown's diagnoses of these forms of the genus Elaphe. 



Coloration. — The ground color of the specimens is an ashy-, 

 brownish- or yellowish-gray with a series of 30-36 dorsal grayish- 

 brown to dark chocolate-brown spots on the body and 9-16 on the 

 tail. In the cephalic half of the body these spots have their anterior 

 and posterior edges concave, i.e., their angles produced, thus giving 

 the spot the shape of a ray's egg; in the caudal part of the body the 

 dorsal spots are more or less quadrate. Occasionally, the 1st and 2d 

 or the 2d and 3d dorsal spots are more or less united. In one speci- 

 men for its entire length (No. 6,136) these dorsal spots are connected 



