400 PROCEEDINGS OF THE ACADEMY OF 



September 7. 

 The President, Dr. Ruschenberger, in the chair. 

 Thirty -one members present. 



On Mermis acuminata. Prof. Leidy exhibited a living speci- 

 men of Mermis acuminata, which had been sent to him for ex- 

 amination, the 8th of last August, by Mr. P. H. Foster, of Babylon, 

 Long Island, N. Y. It was one of two specimens which Mr. Foster 

 had taken from apple worms found concealed in a woollen rag tied 

 around the trunk of an apple tree in his garden. The Mermis is 

 7|- inches long, and had been retained alive in a box with moist 

 sphagnum. It exhibits a condition which Prof. L. had observed on 

 several pi'evious occasions in other species of Mermis. An inter- 

 mediate portion of the body, apparently from injury, had died 

 and was decomposed, while the extremities held together b}^ the 

 integument were still alive and active. This condition has been 

 observed to be maintained for some time, that is to say, for some 

 weeks. 



September 14. 

 The President, Dr. Ruschenberger, in the chair. 

 Thirty-six members present. 



September 21. 

 Dr. Carson, Vice-President, in the chair. 

 Forty-nine members present. 



Variations in the StipuJar Sjnnes of Eobinia Pseud-acacia. 

 Mr. Thomas Meehan referred to the thorns of the yellow locust, 

 which, as usually seen, were about a quarter of an inch long, and 

 nearly as wide at the base; triangular in shape. At the meeting 

 of the American Association at Detroit he collected specimens, 

 one of which he exhibited, with slender spines, about three- 

 quarters of an inch long. Since then, in the vicinity of Chicago, 

 he had noticed that there was considerable variation in the direc- 

 tion of long and slender spines. In his own vicinity he had since 

 noted a large number of trees, and some variation, but onl} r to-day 

 had he found one with long, slender spines, and that was even 

 longer than the case from Detroit, being in some cases a full inch 

 in length. The fact of this great variation was probably new ; 



