1894,] Hydroid; Cold Spring Harbor, Long Island. 27 
PERIGONIMUS JONESII; A HYDROID SUPPOSED TO 
BE NEW, FROM COLD SPRING HARBOR 
LONG ISLAND. 
By HENRY LESLIE OSBORN AND CHARLES W. HARGITT. 
. The authors of this article, while engaged in seaside studies 
at Cold Spring Harbor, at the Laboratory of The Brooklyn 
Institute, found a certain hydroid which is the subject of this 
article. A careful survey of the accessible literature of the 
subject has failed to demonstrate that it has been previously 
described, though its very common occurrence together with 
the ease of its capture render it remarkable that it should have 
escaped the hands of the collector heretofore. It is a very 
interesting species on account of the very primitive state of 
development of the integument, if we may so call the theca or 
skeleton, and hence of interest to the biologist, for whose sake, 
