MICHIGAX ACADE>n Ol" SCIENCE. 59 



The secondary reptilian species oi' this series arc two turtles. One 

 of these, Chrysemys cinerea, was rather abundant in the dee)j water 

 of the waterlily associations and was occasionally found in the larger 

 beach pools. The other, Chelydra .serpeniiua, was too rare in the region 

 (see annotated list) to have any large connection at present with the 

 general ecology of tlie amphibians and other reptiles. Both species of 

 turtles are omnivorous (see Ruthven. Thomjjson and Thompson, 1912, }))). 

 135, 111 and 1 1-2 for summaries of the food of these species), although 

 they may be dependent upon the primary amjihibians of series 1 as their 

 food includes tad]>oles and tlie bodies of vertebrates dying in the water- 

 lily associations. 



Series 2. Habitat of adults, -icoodlaud ; hahitdt of nnipJii'daii larvae, 

 aquatic. 



AMPHIBIA. 



Primary species Secondary species 



Bufo americanus Ambystoma. jeffersonianuni 



liana cantabrigensis Hyla versicolor 



Hyla pickeringii 

 Acris gryllus 



ASSOCIATEU REPTILIA. 



Primary species Secondary s]Tecies 



Thamnophis sauritus None 



Thamnophis sirtalis 

 Heterodon platyrhinos 

 Natrix sipedon 



The amphibian species of series 2 like those of series 1 require a 

 pond habitat for the eggs and larvae. The tadpoles or larvae of all of 

 the amphibians of series 2 however, transform during the first summer, 

 and with the exception of Acris gryllus, before the first of September 

 (Ruthven, Thompson and Thompson, 1912, pp. 31, il, tS, 45, and 57; 

 Diekerson, 1905, p 156). The more rapid metamorphoses of these species 

 enables them to take advantage of less permanent breeding places than 

 those required by the amphibians of series 1. The transitional habitats 

 seemed the important ones in determining the local distribution of the 

 amphibians of series 2. These species were not as abundant in and 

 about lily ponds and beach pools which adjoined swampy habitats, as 

 near lily ponds and bog pools which adjoined forest and woodland 

 habitats. The upper beach connecting a woodland habitat vi^ith a lily 



