224 RESEARCHES IN HELMINTHOLOCY AND PARASITOLOGY. 

 [November. 1888. No. 567. See Bibliography.] 



Extract from Fauna of Ikach Haven, N. f. — From an oyster bed 

 we took up some young oysters, an inch to two inches long, with 

 the shell perforated by the ' ' drill, ' ' Uromlpinx cincrca. The perfora- 

 tion, made in the vicinity of the adductor muscle, about admits an 

 ordinary bristle. An oyster-catcher, James R. Gale, informed us 

 that the " drill " was introduced into the locality with spat brought 

 from the coast of Virginia. With the Urosalpinx we took another 

 snail, Anachis similis, which Mr. Gale assured us was more de- 

 structive, as a borer, to young oysters than the former. Another 

 snail which we took, the Eupieura caiidata, Mr. Gale says has the 

 same habit. 



Attached to oysters were also found a great profusion of the 

 polyzoon Vesiciilaria dichotoma . 



The shrimp is infested to a wonderful degree with a parasitic 

 crustacean, Bopyrus palcenioneticola. 



[January, 1889. No. 571. See Bibliography.] 



On Several Gregarines and a StJigtilar Mode of Conjugation of One 

 of Them. — Prof. L,eidy 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, Nyctobates 

 pennsy/vanicHs, 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 some- 

 what 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 0.6 to 0.15 mm. (Drawing, etc. ) 



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

 peculiar. In the pairing of most described species of Grcgari)ia, 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. In the species under consideration I have observed that the 

 pairs conjoin, as represented in the accompanying figure, with the 

 heads together and the bodies side by side. In numerous instances 

 the position was invariable, and in all, the couples variably differed 

 in size. Thus in one pair the longer individual was 1.75 mm. long 

 and the smaller one 0.75 mm. long, and in another pair the larger 

 individual was 2 mm. long and the other 1.75 mm. (Drawing.) 



