Stodder.] 302 [October 9, 



itnirJentata, mulfideniata, and otliers, remains of Avliicli were found in 

 the lower portions of the heaps, can only exist in hard wood growths. 

 The portion of the island where these heaps occur is at present cov- 

 ered with large spruce growth. The Quahog, found plentifully in 

 the heaps, is extremely rare in Maine. Thus we have a change of 

 vegetation, a change of certain species of animals, an evidence of 

 extensive erosion of the hanks, an absence of articles that one would 

 be likely to find in deposits of recent formation, all indicating ex- 

 treme age. Of course, these evidences do not indicate the age of the 

 shell heaps, further than to show that hundreds, perhaps thousands of 

 vears, may have elapsed since they were first commenced. The 

 Danish archa3ologists regarded similar heaps in Denmark as older than 

 the stone age; in fact, as among the earliest evidences of the presence 

 of man. 



A short discussion ensued upon the probability that the shell heaps 

 rested ujDon the primitive soil. Mr. Scudder wished to know what 

 had become of the vegetable mould which supported the hard wood 

 growth, beneath which the land shells found at the bottom of the 

 shell heap lived. Dr. Pickering believed that vegetable mould would 

 disappear after the lapse of ages by the action of the elements, and 

 Dr. Jackson spoke of the chemical means by wliieh this would be 

 brought about. 



Section of Microscopy. October 9, 1867. 



The Curator in the chair. Thirteen members present. 



Mr. C. Stodder read a note on JVavicida Carassius. 

 Ehrenberg's description is as follows : — "Ventricose, inflated, 

 broadly lanceolate, with the ends suddenly contracted into 

 short, conical beaks ; strise wanting, or indistinct." As seen 

 with Tolles' one-tenth unmersion lens, Mr. Stodder adds to 

 the above description, — striae diagonal or quincunx, like 

 many of the Pleurosiginas, very faint and fine, nearly ninety 

 thousand to the inch ; length of frustule about three one- 

 thousandths of an inch; locality, Bridgeton, Me. Recent 

 si^ecimens were communicated by Dr. Thos. F. Perly. 



He remarked that the objectives used by Ehrenberg, when 

 he published his great work on Infusoria, were undoubtedly 



