136 



HERPETOLOGY OF MICHIGAN. • 



manner and then retreated. Tlie filling-in process was the same 

 as that observed for Graptemvs and Aspidonectes. 



"The nest was in gravelly sand on the side of a railway embank- 

 ment, sej^arating the lake from a swamp. An examination of the 



Fig. 46. Distribution of Chelydra serpentina. 

 Horizontal ruling, specimens examined; vertical ruling, reports only. 



nest revealed a broad fnnnel shaped depression, about a foot in 

 diameter, at the apex of which a tnnnel, about fonr inches in 

 diameter, led diagonally into a wider expansion of irregular shape 

 and about a foot beneath the general ground surface. The tunnel 

 was obstructed b}^ a stout stick and was consequently turned some- 

 what to one side. In the expansion and communicating tunnel 



