ALCTONAEIA. 355 



and measure -4 to '6 by -035 to "06 millim. [Comparing Stu 

 species S. grayi with this species, it appears to correspond closely 

 with it, but is perhaps distinct by virtue of the smaller size of the 

 spicules and the simple character of their tubercles, as stated above.] 



Ilab. Port Molle, Queensland, L2 20 1ms., bottom rocks and 

 coral ; Arat'ura Sea, off N.W. coast of Australia, 32-36 fms., bottom 

 sand, mud, and shells. Also Mermaid Strait, X.Y\'. Australia (Studer). 



Obs. It is interesting to note that it is the specimen which comes 

 from a rocky bottom which lias the simple, moderately long, cylin- 

 drical stem resembling that of the type specimen, while that which 

 came from a loose bottom (sand &c.) has a long spatulate termina- 

 tion, well adapted for maintaining the colony in an upright position 

 in this less stable material. 



It seems extremely probable from the account given by Messrs. 

 Milne-Edwards and Haime (7. c.) of the external characters of their 

 Coelogorr/ia palmosa , that it isgenericallyidenl icalwith Solenocaulum ; 

 but finding a very different spiculation indicated in a Paris slide 

 in this Museum, which professes to belong to the species, I prefer 

 to follow Studer in leaving the question for future investigation. 



31. Leucoella cervicorni-. 

 Leucoella cervicornis, Gray, Ann. 8f Mag. N. H. (4) v. p. 408. 



A Briareacean intermediate in its characters between Suberia, 

 Studer (MB. Ak. Berlin, 1878, p. 666), and Solenocaulum, Gray. 

 Its most striking external feature is the broad posterior space devoid 

 of polypes and (in the dry state, at any rate) indented by a wide 

 groove. In the type specimens in the British Museum the verrucas 

 mostly have rounded blunt terminations, about 1 millim. in maxi- 

 mum height ; in a specimen, however, contained in the present 

 collection they are mostly pointed and very prominent, viz. 2 millim. 

 high in some cases. Whereas also in the type specimen the colour 

 is somewhat pale umber-brown, in the present specimen the colour is 

 very dark umber-brown, becoming almost black at the tips of the ver- 

 rucas : in this specimen the anterior aspects of the tips of the branches 

 are almost devoid of verrucas and usually much flattened, while the 

 verrucas on the anterior and lateral faces of the other parts are placed 

 at distinct intervals; the latter are closely set in about equal pro- 

 portions over all parts of the anterior and lateral surfaces of the 

 stem and branches. The axial spicules (i.) in both specimens are 

 cylindrical, pointed at the ends, and covered with small sharp 

 tubercles ; size -35 to -42 by '024 to -027 millim. The cortical spicules 

 are either (ii.) fine, long, fusiform, tapering to points at both ends, 

 provided with numerous, but distinct prominent tubercles, '28 to "42 

 millim. by - 053 to *08 millim., or (iii.) squat fusiform, with the ends 

 more rounded than in (ii.), with the tubercles stouter and blunter 

 but crowded together ; size -14 to -28 by -053 to -07 millim. This 

 specimen furnishes us with a locality for the species, that of the 

 original specimen not being known. 



Hab. Port Denison, Queensland, 4 fms. ; bottom rock. 



2a2 



