March, 1888.] Elliott society. 201 



ness and laigesize of tlie muscle in the former, but a great development of the 

 mantle or gills, which, I believe, is caused by the necessity for having a larger 

 and more perfect breathing apparatus to reach the oxygen in its muddy bed. 



In the few clams which are found in these ponds, I note also the excessive 

 development of the adductor muscle, which renders them inedible, for almost 

 aU of the animal is muscle. They can live farther down in the mud than the 

 oyster, and it may be of interest to know that they keep up a constant circula- 

 lation of water in and out of their holes by the use of this jet, I have found 

 the cliunfrom afoot to two feet under the mud ; the oyster succumbs on sink- 

 ing more than 8 to 12 inches. 



APKIL 26th, 1888. 

 Vice-President H. P. xIrcher in tlie Chaii-. 

 Books Received. 



Royal Society, London : Proceedings, No. 263. 



Elisha Mitcliell Scientific Society, Chapel Hill, N. C. : Journal, 

 1887, Part 2. 



Joui-nal of ComparatiYC Medicine and Surgeiy, Philadelphia : 

 Vol. IX, No. 2. 



Museum of Comparative Zoology, Cambridge : Bulletin, Vol. 

 Xin, No. 8, and Vol. XIV, No. 1. 



California Academy of Sciences : Bulletin, Vol. 2, No. 8. 



American Philosophical Society, Philadelphia : Report on Scien- 

 tific Value of Volaptik. 



A communication from the American Philosophical Society of 

 Philadelphia, concerning the scientific value of Yolap'iik^ was read 

 and referred to Prof. Hem-y E. Shepherd. 



VOL. n. 26 rublished June, 1888. 



