392 Mr. H. J. Carter oji DeejJ-sea 



face are nestled parasitically many small crustaceans, which 

 have been named, described, and figured by the Rev. Thomas 

 E. R. Stebbing, M. A. (' Annals,' 1875, vol. xv. p. 184, pi. xv. 

 fig. 1; &c.). 



POLYMASTINA. 



{(laa-TO'iy nipple.) 



I would propose this name for a group of sponges which 

 provisionally might be placed before Donati'na, in the suborder 

 Suberitida, under the order Holorhaphidota in my classifica- 

 tion {' Ann.' 1875, vol. xvi. p. 190), characterizing it by a 

 smooth appendiculate (mastophorous) surface, for the most 

 part sessile, sometimes stalked ; composed internally of a 

 radiating structure consisting of bundles of large, smooth 

 pointed, fusiform spicules, for the most part round or inflated 

 pin-like at the inner or larger end, sometimes acerate or sharp 

 at both ends ; faced with a smaller spicule of the like form, 

 which, together with the larger ones, project more or less 

 beyond the surface, so as to give it the villous character above 

 mentioned. More or less hollow or soft internally, or in- 

 tensely compact and hard throughout. 



Of these. Polymastia hrevis^ hdbosa, mamillaris^ ornata, and 

 rohusta, Bk. (o^). cit. vol. iii. 1874), also ThecopJiora semi- 

 snbentes, Sdt., T. ibia, Wy. Thomson, Rinalda uberrima^ 

 Sdt., with the, to me, stalked forms, viz. Polymastia stipi- 

 tata^ n. sp., Cometella simjjlex, n. sp., snad Podospongta Lovenn, 

 Bocage, together with the laminiform Latrunculia cratera, 

 Bocage, have all, with the exception of Cometella simplex^ 

 which seems to have come from the " chops " of the English 

 Channel, been dredged up at various stations respectively be- 

 tween the north of Scotland and the Faroe Islands, especially 

 at station 65, in 345 fathoms. 



Other species of Polymastia have been described and illus- 

 trated by Dr. Bowerbank {pp. cit.)^ viz. P. conifera^ radiosa^ 

 and spimdaria, also by Schmidt (Atlantisch. Spongienf. 

 1870), viz. Radiella spinidaria^ Sol., Eumatia sitiens and 

 the stalked sponge Cometella stellata perhaps ; while Bal- 

 samo-Crivelli in 1863 (Atti della Soc. Ital. di Scienze, vol. v. 

 tav. vi. figs. 10-17) ^^rs^ of all figured the species Suberites 

 appendicitlatus. It is possible that several of these species 

 are but different forms of the same ; hence further observations 

 may considerably reduce their number. 



The second kind of sponges included under Polymastina is 

 the hard, solid, compact one, but still presenting the same 

 kind of spicules and villous surface. One of these I described 

 and illustrated in 1870 under the name of Trachya permicleata 



