696 Proceedngs of Scientific Societies. [August, 1882. 



asbestos could be supposed to influence the crystallization of the 



Dr. Koening stated his belief that the coloring matter of tour- 

 maline is entirely organic, and Dr. Leidy confirmed the belief 

 from his experience of its destruction by heat. 



Professor Heilprin remarked upon the erosion of their western 

 banks by streams flowing from the poles to the equator, and of 

 their eastern banks by streams flowing in the reverse direction. 

 This Was caused by the earth's rotation, but he suggested that 

 for the same reason streams flowing from east to west ought to 

 have a slower motion than those moving from west to east. 



Dr. Parker recorded an anomaly in the common extensor ten- 

 don of the fore-limbs of a porcupine. The middle digit was un- 

 supplied, the tendinous slip belonging to it being sent to the fourth 

 hich was thus furnished with two slips. 



March 7. — Mr. Meehan spoke of the^difference in time between 

 the ripening of the male and female flowers of the silver maple. 

 Most of the male flowers on weak shoots open a week or two 

 earlier than the female, leaving the work of fertilization to be per- 

 formed by the few male flowers which, being on stronger 

 branches, expanded the same time with the female. 



Dr. Leidy called attention to the occurrence of Ba 

 at Atlantic City. He believed this worm to be near to the 

 Nemerteans. Pie also praised the excellence of soup made from 

 Soltn anis. Dr. Leidy also -ta:- d that he had found Scolithus in 

 pebbles of Potsdam sandstone from near Philadelphia. 



Professor Lewis exhibited a large pebble showing glacial 

 grooves. 



March 16.— Dr. Horn spoke of the impalement of grasshoppers 

 upon the echinocacti in Arizona by the action of shrikes or 

 butcher-birds. 



Mr. Ryder stated that the green color of oysters was not due 

 to salts of copper, but probably to chlorophyll, so that green oys- 

 ters were perfectly fit for food, as he had proved himself. 



The president stated that enough copper to color an oyster 

 would certainly kill it. The green color might be the zoospores 

 of Ulvalatissima. 



Professor Heilprin drew attention to the occurrence of an am- 

 monite in situ in pieces of rock from the Tejon group of Califor- 

 nia. As all the other fossils in this rrroup were Tertiary, the 



