NATURAL SCIENCES OP PHILADELPHIA. 295 



November T. 



The President, Dr. Ruschenberger, in the chair. 



Twenty-four members present. 



The death of Wilhelm Ritter von Ilaidinger, a correspondent 

 of the Academy, was announced. 



Prof. Cope exhibited a specimen of a Galeodes, probably G. 

 pallipes of Say, taken in the town of Denver, Colorado, by Dr. 

 Gehrung. xVccording- to that gentleman, it was common in that 

 place in houses, and was an euem}^ and destroyer of the Cimex 

 lectulariws (bedbug). In captivity, it showed a preference for them 

 as food, and crushed them in its short cheles, preliminar3^ to suck- 

 ing their juices. 



Mr. Thomas Meehan said that while travelling throu2;h a wood 

 recently he was struck in the face bj^ some seeds of Ilamamehs 

 virginica, the common Witch Hazel, with as much force as if 

 they were spent shot from a gun. Not aware before that these 

 capsules possessed any pi'ojecting power, he gathered a quantity 

 in order to ascertain the cause of the projecting force, and the 

 measure of its power. La3'ing tiie capsules on the floor, he found 

 the seeds were thrown generally four or six feet, and in one in- 

 stance as much as twelve feet awa}'. The cause of this immense 

 projecting power he found to be simply in the contraction of the 

 horny albumen which surrounded the seed. The seeds were oval, 

 and in a smooth bony envelope, and when the albumen had burst 

 and expanded enough to get just bej'ond the middle where the 

 seed narrowed again, the contraction of the albumen caused the 

 seed to slip out with force, just as we would squeeze out a smooth 

 tapering stone between the finger and thumb. 



November 21. 

 The President, Dr. Ruschenberger, in the chair. 

 Twenty-six members present. 



The following paper was presented for publication : — 



"Notes on Feldspars and some other Minerals of Philadelphia 

 and vicinity." By Theo. D. Rand. 



Mr. Thomas Meehan said that of all the problems that faced 

 the botanist, few seemed more impenetrable than the law which 

 governed the angular divergence in the branches of plants. Sorde 



1872.] 



