112 Mr. H. J. Carter on 



Ftff. 11. Cypidium imtrinum, X 300. 



Fig. 12. Colpidium striatum, X 450. 



FI(J. 13. Diplomasfax frontata. Ventral, X 250. _ 



Fig. 14. Diphnnasf a. v' frontata. Reproductive fission. 



Fif/. 15. Hidiohalanti'um atjile. Dorsal, X 300. 



Fig. 16. Histiuhalantium agile. Lateral, X 450. 



Fig. 17. Rhahdosttjla pusilla, X 500. 



Fig. 18. VorticcUa Lemme, X 360. 



Fig. 19. Balanitozoon agile, X 810. 



Ftg. 20. Uroleptus Sphagni, X 135. 



Fig. 21. Vaginicola ampulla, X 137. 



Trenton, New Jersey, U. S. America. 



XII. — Descriptions of Sponges from the Neighhourhood of Port 

 Phillip Heads., South Australia, continued. By H. J. 

 Caktee, F.R.S. &c. 



[Continued from p. 53.] 



Fam. 2. Suberitida. 



Group 11. SUBERITINA (new group). 



(Proposed in.stead of the original groups 10, 11, and 12, 

 viz. Cavernosa, Compacta, Laxa, and the subsequently added 

 group, viz. Subconipacta, which the group Suberitina is in- 

 tended to include as subdivisions.) 



Spirastkella, Sdt. (Spongf. Kiiste v. Algier, 1868, 

 p. 17, taf. iii. fig. 8). 



General Observations. 



This genus is chiefly characterized by its spiculation, con- 

 sisting of a pin-like skeletal and spinispirular flesh-spicule, 

 the latter, like most flesh-spicules, congregated more or less 

 thickly into a layer on the surface ; hence Schmidt placed it 

 among his '' Corticate" (!), our Pachytragida. But inasmuch 

 as there are two kinds, if not species, of this sponge which 

 possess the same form of spiculation, it becomes necessary to 

 seek in the size of their spicules, their structures, and their 

 adult forrns respectively for their differences. Thus while 

 the spicules in the original species, viz. Spirastrella cunctatri.c, 

 Sdt., may be set down as longer and thinner, those of the 

 other kind or variety, which we shall term Spirastrella cunc- 

 tatrixy var. rohusta, are shorter and stouter (a fact of general 

 occurrence too with adidt spicules of all kinds even in the 

 same specimen, as I have often stated). 



