PROCEEDINGS 



OF THE 



ACADEMY OF NATURAL SCIENCES 



OF 



PHILADELPHIA. 



1889. 



January 1, 1889. 

 The President, Dr. Joseph Leidy, in the chair. 

 Seventeen persons present. 



On several Gregarines, and a singular mode of conjugation of one 

 of them. — Prof. Leidy communicated the following on some species 

 of Gregarina. : Among coleopterous insects the family of Tenebrion- 

 idae appears to be constantly infested with gregarine parasites. A 

 remarkable species observed in one of our common beetles, Nye- 

 tobates pennsylvanicus, I propose to distinguish by the name of 

 Gregarina philica. The body is elongated clavate, variably 

 thickened and rounded in front, somewhat tapering behind, and with 

 the posterior end conical. Cephalic division campanulate, with the 

 summit somewhat prolonged and surmounted by a horizontal circular 

 disk with a rounded, milled border. Conjugating individuals with 

 the cephalic extremity conical and simple, or without the terminal 

 disk. Length from 0*3 to 2 mm. ; breadth - 6 to 015 mm. 



In conjugation the species is remarkable and so far as I know 



peculiar. In the pairing of most described species of Gregarina, two 



individuals, commonly of the same size, conjoin in the same line, the 



cephalic extremity of one attached to the caudal end of the other, 



2 



