25 



University of Michigan 



the next habitat (41), except that the yellow birches were 

 almost entirely replaced by the beeches (Fagus grandifolia), 

 and the hemlocks were considerably more abundant. 



Table V. Distribution of Land Shells 



Larger Forms : 

 Pallifcra dorsaUs 

 Polygyra profunda 

 Polygyra fraierna 

 Polygyra albolabris 

 P. albolabris maritivia 

 Pyramidula altcrnata 

 Agriolimax camp est ris 

 Succinea avara 

 Succinea rctusa 

 Physa gyrina 



Smaller Species: 

 Zonitoides milium 

 Vertigo fridentata 

 Gastrocopta corticaria 

 Vitrea rhoadsi 

 P. cronk. catskillcnsis 

 Vertigo gotildii 

 Eu. chers. polygyratus 

 Strobilops virgo 

 Zonitoides arborca 

 HcUcodiscus parallelus 

 Gastrocopta contr.acta 

 Buconulus fulvus 

 Vitrea indentata 

 Gary, exile canadensis 

 Vitrea hammonis 

 Vitrea ferrea 

 Gastrocopta tappaniana 

 Vitrea binneyana 

 Vert, ventricosa elatior 

 Carychium exiguum 

 Pisidium abditum 

 L. obrussa periinsulcc 

 Gochlicopa lubrica 

 Zonitoides cxigua 



* I = locally. 



HARDWOOD 



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