BRITISH ZOOPHYTES. 93 



1. C. ACUMINATA, Aid. 



C. tenuis {V.B.), Laomedea acuminata {Aid., T. S. W., 

 McA.), Wrightia acuminata {Ar/.). 



Hab. : CuUercoats {Aid.), Firth of Forth {T. S. W.). 

 Height about | in. Stem ringed almost throughout. 

 Calycles membranous, with linear sti'iations tapering 

 to a point, presenting, when closed, the appearance of a 

 closed Chinese umbrella. Polypites with about 20 very 

 long, webbed tentacles. Gonothecae large, pedicellate, 

 cylindrical. The tentacles are webbed in a very dis- 

 tinct manner to about one-sixth of their length, the 

 webs being " studded with thread cells." '' The cells,^' 

 says Alder, " are extremely elastic and membranous, 

 changing form with the polyp, and scarcely to be dis- 

 tinguished from it when alive, excepting at the apex 

 when the animal is withdrawn. ^^ 



2. C. EEPENS, All. 



Hab. : Firth of Forth (All). 



In this species the calycle is " crowned by long con- 

 verging segments which, on the retreat of the polyp, 

 form a true operculum." The tentacular web is not 

 so fully developed as in the preceding species. 



Described by Professor AUman in "Not«s on the 

 Hydroida," in the Ann. of Nat. Hist., July, 1864. 



3. C. Tderita, Hincks. 



Hab. : Belfast Lough {Prof. W. Thomson). 



Described by Mr. Hincks (B. H. Z., 190, pi. xxxvi 

 2) from drawings supplied by Prof. Thomson. The 

 species appears to unite the characteristics of G. acii- 

 ininata and C. repens. 



G-ENUS II. Zygodactyla, Brandt. 

 Stem simple or branching, rooted by a filiform stolon. 



