344 COLLECTIONS FROM MELANESIA. 



Hub. "Warrior Reef and Prince of "Wales Channel, Torres Straits ; 

 in the latter case from 7 to 9 fms., bottom sand (actually attached 

 to a stom). 



This is a very beautiful and attractive species, the mode of 

 branching and the proportions of the branches being graceful 

 and the colours very vivid. 



Of the three dry specimens obtained (i.) deep yellow, is 550 millim. 

 (22 inches) high by 325 millim. (13 inches) in extreme diameter ; 

 (ii.) lemon-yellow specimen, 475 by 275 millim. (19 by 11 inches) ; 

 (iii.) reddish specimen, 475 by 387 millim. (19 by 15^ inches). A 

 young specimen preserved in spirit of the same colour as (i.), and 

 measuring 145 millim. high by 30 millim. maximum lateral ex- 

 panse, is distinguished by slenderer habit. 



Of the double-headed spicules which Verrill has found in many 

 Leptogorgice I have seen none here, though sometimes almost de- 

 ceived by pieces of broken fusiform spicules, consisting of a smooth 

 median portion and a whorl of tubercles left at each end of it. I 

 have no doubt as to the specific identity of the above specimens. 

 In the main external features of the corallum, and the forms and 

 proportions of .the different kinds of spicules, they agree substan- 

 tially with one another, as may be seen by the few differences by 

 which it has been found possible to distinguish the two varieties ; 

 the colour is the only serious difficulty in the way of uniting these 

 two varieties, and is shown not to be of specific importance in this 

 case by the fact that red spicules do occur in the cortex of both 

 specimens of the yellow variety, and that in that of the main 

 branches of the red form there are almost, if not quite, as many 

 yellow as there are red spicules, some individual spicules being 

 transitional in colour. 



In its manner of branching the species belongs to one of the 

 less common types of this large genus. Of other Australian species 

 L. divergens, Studer (aIB. Ak. Berlin, 1878, p. 655, pi. iv. fig. 21), 

 from N.W. Australia, is a very different form, if it be a Leptogorgia 

 at all ; its polype-spicules are very large and the mode of branching 

 dichotomous. Sydella australis, Gray (P. Z. S. 1872, p. 747, pi. lxiii. 

 figs. 8, 9), from Sydney, only known from a drawing, is perhaps 

 another Australian Leptogoryia distinguished by a long termination 

 to the branch! cts bare of cells. 



PSAMMOGORGIA, Verrill 

 17. Psammogorgia rectangular is. (Plate XXXVI. figs. A, a, a''.) 



Corallum erect, branching in ono plane ; the main branches pin- 

 nate on one side with short claviform twigs, projected almost at 

 right angles co branches, at intervals of 8 to 20 millim. 



Stem cylindrical, about 1-25 millim. in diameter. Branches 

 rather compressed from front to back; average diameter from side 

 to side 2 millim. ; diameter of small branches at origin 1 millim., at 



