16S CORYNE VAGINATA. 



3. COUTNE VAGINATA, H/'uch. 

 Plate IV, figs. 8, 9. 



CoRVNE PDsiLLA, var. MuscoiDEs, — JoluisloH, Biit. Zoopli., 1847, p. 12, p]. vi, figs. 4, 5. 

 CoKYNE VAGINATA, — Hiticks, in Anu. Nat. Hist, foi- 1866. Brit. Hydr. Zooph., p. 41, pi. 

 viii, fig. 1. 



TROPHOSOME. — Htdrocaulus rising to a heiglit of from two to tliree inches, 

 alternately branched, each of the main branches sending off numerous short alternate 

 simple ramuli ; peeisaec distinctly and regularly annulated. Hydeanths borne upon 

 a narrow neck, which is surrounded by a loose membranous sheath, derived from the 

 perisarc, and losing itself on the body of the hydranth ; tentacles about twenty. 



GONOSOME. — Spohosacs globular, developed from the body of the hydranth, 

 each si)ringing by a short peduncle from the axil of a tentacle. 



Colour. — liydranths and sporosacs pale pink, perisarc light brown. 



Development of Gonosome. — Summer and autumn. 



Habitat. — Attached to sea-weeds and to the sides of rock pools, near low-water mark. 



Batliij metrical Distribittion. — Lower part of Litoral zone. 



Localities. — Coasts of Devonshire, Rev. T. Hincks and G. J. A. ; Coast of Cornwall and 

 Southern and Eastern Coasts of Ireland, G. J. A. ; North-east Coast of Ireland, Mr. William 

 Thomson. 



Coryne va(jinata forms branching hydrosomes, longer, looser, and more flexile than those of 

 Coryne imsilla, while its large size and the symmetrical distribution of its branches renders it a 

 conspicuous and beautiful object in the clear rock pools where it is rooted. 



One of its most striking characters is the sheath-like extension of its perisarc, by w'hich the 

 neck of every hydranth is invested in a loose transparent pellicle, a feature to which attention was 

 first called by Mr. Hincks. This is plainly a continuation of the most external or oldest layers of 

 the perisarc, which in the young state of the hydranth constitute an external capsule, in which 

 the entire hydranth-bud is included, and within which this bud passes through the earlier stages 

 of its development. 



It is a very abundant and characteristic species on the southern shores of Devonshire and 

 Cornwall, and on the southern shores of Ireland. It occurs also on the eastern shores of Ireland, 

 where I have found it in considerable abundance in Dublin Bay, while it has been obtained by 

 Mr. William Thomson on the same shores, as far north as Strangford Lough. I have never met 

 with it on any part of the Scottish coast or on the coasts of the adjacent islands, the genus being 

 there chiefly represented by Coryne pusilla. 



