822 Mil. .1. lUTCIIIK ox UYDIIOIUS [^^'IV 24, 



In the structure of the opercuhiin A', turhinata appeai-s to 

 differ from S. verduysi Nutting (1904) — regarded by Billard 

 (15)08) as a synonym — for in the latter, as Congdou states (1907, 

 p, 482), and as careful examination of the lateral aspect of s])eci- 

 niens from Cape Verde Islands, in my collection, shows, the 

 operculum is furnished with a large abcauline and two snialler 

 latero-adcauline valves. 



The protractor of the hydranth, which possesses only a small 

 ])lind-sac, is attached to the hydi-othecal wall at the intrathecal 

 ridge. 



Localities. 8tt. 15 and 16, Ravenshaw Island, 8ir John Malcolm 

 Island, and Alligator Rock, 5 to 18 fathoms, rock and sand, or 

 rock and mud ; not common. 



Family P l u m u L A ii i b .*:. 



Plumulauia setacea Linnanis, 1758 (?). 



A single immature colony, 15 nun. high, identical in all respects 

 with North 8ea specimens. I have written the designation with 

 a mark of interrogation on account of the impossil)ility of dis- 

 tinguisliing the tro})hosome of this small variety fiom that of 

 P. strictocarjia Pictet (1893), from Anil)oyna. 



Locality. Maskos Islands, 3 to 2(3 fathoms, rock and sand, or 

 rock and mud. • 



Plumulauia sp. 



An unidentifiable fragment, the structures of the stem and 

 hydroclfides of which resemlile those of P. setacea, but the frag- 

 ment shows traces of branching, and the hydrotheca of having 

 a slightly concave contour. 



Locality. St. 32, Hastings Harbour, shore to 20 fathoms, rock 

 and sand. 



Antexella secundaria (Jmelin, 1788-93, 



The nematocysts of the nematophores measure 12 ^i by 4 ^/, 

 agreeing with Warren's measurements of those in A. tiatalensis, 

 which 1 regard as a synonym. There are about 18 tentacles. 



Locality. St. 1, east of Tavoy Island and Port Owen, 4 to 12 

 fathoms, sand and broken shells, and mud ; not common, on 

 Idia jn-istis. 



Lytocarpus PENNARius Linua^us, 1758. 



A widely distiibuted species, lepresented by several fine 

 colonies, one of which reached a height of 95 cm. Apai't from 

 the prominent anterior tootli, that on the margin of the hydro- 

 theca second from the stem is distinctly the largest. It forms 

 the highest point on the outwardly curved niaigin of the hydro- 

 theca. There is, however. ,some variation in the prominence of 



