

io6 



CHAS. W. HARGITT. 



when the stem finally contracts in a way to suggest that of Vorti- 

 cella, though without the coiling of the stem as in the latter 

 organism. I am inclined to regard the organ as probably pos- 

 sessed of a tactile function. 



Ectopleura. — While dredging off Gay Head on board the 

 "Fish Hawk," July 15, 1907, I was fortunate in discovering on 

 the carapace of a small specimen of the common spider crab, 

 Libinia, among other hydroids not uncommon on this creature, 

 including a species of Campanularia and Halecium articulosum, a 

 small tubularian-like hydroid having a very short stem, large 

 hydranth, the latter being crowded with racemose clusters of 

 medusa-buds, some almost ready to be liberated. In appearance 

 the hydranth, in its size and general aspects, was much like 

 Tubularia crocea, though rather larger, and the oral tentacles 

 fewer in number. A closer inspection under a lens, and later 

 under the low power of the microscope, soon made it evident 



^~»5 



FlG. 8. Ectopleura prolifica. 



that the specimen did not belong to Tubularia, and the liberation 

 soon after coming to the laboratory of several medusae made this 

 doubly certain. An examination of the medusa soon showed 

 that we had under examination a species of Ectopleura. Since 

 no description of the hydroid of this genus has been recorded 

 from this region it seemed worth while to have a careful sketch 

 made of it, which is shown in Fig. 8. 



The following are the chief points of diagnostic importance. 

 Stem of hydroid very short, hardly exceeding 5 or 6 mm., and 



