348 Mr. H. J. Carter on some West-Indian 



Meanwhile Albany Hancock (in 1867) found, described, 

 and figured the spinispirula in several "Excavating Sponges " 

 ('Annals,' vol. xix. p. 229, pis. vii. and viii.). 



Again, in 1878 Schmidt figured the spinispirula of a sponge 

 which he described under the name of Hpirastrella cunctatrix 

 (Spong. Kiiste v. Algier, S. 17, Taf. iii. fig. 8), likening it to 

 the one from Cyprus, and also tliat of Tethya histellata 

 (Spong. Adriat. Meeres, S. 45, Taf. vii. fig. 1) ; lastly, in 

 1870 he gave this form for the flesh-spicules of his Chondrilla 

 'pltyllodes and Vioa Johnstonii respectively (Spong. Atlant. 

 Gebietes, Taf. vi. figs. 1 and 18). Here it might be observed 

 cursorily tliat, however much the stellate and spinispirular 

 flesh-s))iculcs may be but transitionary forms of one another, 

 as stated by Schmidt {op. cit. S. 5), yet the same cannot be 

 said of the acerate and pin-like spicules which respectively 

 characterize his Vioa Johnstonii of 1862 (Spong. Adriat. 

 Meeres, S. 78, Taf. vii. fig. 17) and that of 1870 (L c), 

 albeit both are excavating sponges, and both possess the same 

 beautiful carmine colour. But neither colour nor habit are 

 always of much value in a specific point of view ; for the 

 Australian species, viz. Alcyoniiun p>urpuretmi of Lamarck, 

 which is also a Suberitc, and another Australian species in the 

 Liverpool Free Museum, although equally carmine in colour, 

 are difterent in spiculation, if not in habit also, from the pre- 

 sence of the spinispirula in the former with a fine structure, 

 and the absence of it in the latter with a gritty one of adven- 

 titious matter. Hence I should be inclined to change the 

 name of Schmidt's Vioa Johnstonii of 1862 to that of Vioa 

 Schmidtii, which in the form of its skelcton-spicule, viz. an 

 acerate, agrees with my Rhaphidhistia sjiectahilis of the Mau- 

 ritius ('Annals,' 1879, vol. iii. pi. xxvi. figs. 13 and 14). 

 The spinispirula, under various forms, is so often combined 

 with a pin-like skeletal spicule, and the latter is so generally 

 characteristic of the Suberite-sponges, that we cannot help 

 connecting them with this kind of spiculation ; at the same 

 time it is not always the case, as the occurrence of an acerate 

 form in the instances just mentioned proves. To be able 

 to demonstrate a corky texture in sponges which hardly 

 exceed a mere film in thickness, as in Rhai^hidhistia specta- 

 bills, which possesses the longest and most beautiful spini- 

 spirula that 1 have ever seen, is of course impossible ; hence 

 the spiculation alone here remains for guidance. 



Having mounted fragments of many Suberites for the pur- ■ 

 pose of proving what 1 have above stated — that is, to see 

 if they contained any fiesh-spicnle besides the pin-like skeletal 

 one, — I will give a list of those that 1 myself have examined 



