CAMPANULINA REPENS. 189 



still more delicate towards the top, where it collapses and 

 is folded together and creased so as to form a conical apex, 

 which serves the purpose of an opei'culum. Mr. Alder 

 describes the margin as slightly crenulated. I believe, 

 however, that there is no true crenulation, but that the 

 appearance is due to the points formed by the folds of the 

 membrane. 



The capsules make their appearance, according to Van 

 Beueden, in the month of June. I have only seen C. acu- 

 minata alive in an aquarium, where it covered profusely 

 a deserted univalve shell ; and I have seldom witnessed a 

 more remarkable display of Hydroid beauty. 



Hob. On an old shell of Fusus antiquus from deep water, 

 Cullercoats (J. A.): on an old oyster-shell from the Firth 

 of Forth (T. S. W.). 



[Coast of Belgium, on shells, stones, and w r eed (Van 

 Beneden) .] 



2. C. REPENS, Airman. 



" Notes on the Hydroida," Ann. N. H. for July 1864. 



Plate XXXVIII. fig. 1. 



STEM simple or branched, distinctly annulated, branches 

 alternate; HYDROTHEC.E conical, closed by a membra- 

 nous operculum, formed of deep and acute convergent 

 segments ; GONOTHEC^E large, obconic, slightly gibbous 

 at one side near the base, with a short ringed stalk, 

 borne on the creeping stolon and occasionally on the 

 stem; POLYPITES very extensile, with about 16 tentacles 

 alternately elevated and depressed, and united at the 

 base by a very shalloio web. 



GONOZOOID (at the time of liberation) with four very ex- 

 tensile tentacles, which are nodulated by clusters of 

 thread-cells. 



THIS species differs from the last in the following parti- 



