16 Spong. 
XVil. SP0NG1JE. 
Hyalonema aculeatum , p. 19 ; H. heideri, p. 23 ; H. indicum , p. 24 ; H. 
pirum , p. 27 ; H. heymonai , p. 29 ; H. weltneri t p. 30 ; //. masoni , 
p. 31 j if. alcocki , p. 34 ; H. investigator is , p. 37 ; i7. maehrenthuli , 
p. 41 ; jQT. cucumia , p. 45. 
HEXACERATINA. 
[Nothing.] 
TETRAXONIA. 
TETRAXONIDA. 
Tetractinellida ( 13 , 21 , 61 ). 
Merill (47) describes fossil spicules, and establishes — with a ? — 8 new 
species of Ocodia on them. 
Topsent (61) considers Dercitus as a degenerate descendant of the Scini- 
dasterina. 
f Astrophora, n. g., for A. baltica , n. sp. ; Deecke, Mt. Ver. Vorpomm. 
xxvi, p. 169. 
Pcecillastra armata , Hanitsch, P. Liverp. biol. Soc. ix, p. 213, n. sp. 
Topsent, Arch. Zool. exp. iii, gives fall descriptions of the following 
species : — 
Placina monilopha , Schulze, p. 549 ; P. dilopha , Schulze, p. 552 ; P. h i- 
lopha, Schulze, p. 555. 
Placortis simplex , Schulze, p. 557. 
Placinastrella copiosa , Schulze, p. 559. 
Oscarella lobularis, Schmidt, p. 561. 
Dercitus bucklandi , Bowerb., p. 528 ; D. plicatus, Schmidt, p. 531. 
Corticella stelligera , Schmidt, p. 539. 
Corticium candelabrum , Schmidt, p. 543. 
Pcecillastra saxicola , Topsent, p. 584 ; P. amygdaloules , Carter, p. 585. 
Litliistida ( 31 ). 
Rauff (54) divides his Tribus Pcecilocladinidce into two subtribes : (1) 
Eutaxicladince (skeleton composed entirely or chiefly of Ennomo- 
clones). (2) A nomocladince (skeleton composed chiefly of Anomoclones). 
t Anomoclonella } \Pycnopegma } and \Dendroclonella , n. gg. ; Rauff, 
Paloeontogr. xli. 
New species described by Rauff, t. c. :■ — 
t Aulocopella Winnipeg ensis, p. 269 [sep. p. 393]. 
t Anomoclonella zitteli , p. 226 [sep. p. 350]. 
t Pycnopegma pileum, p. 233 [sep. p. 357] ; +P. callosum , p. 236 [sep. 
p. 360]; P. stromatoporides, p. 239 [sep. p. 363]. 
\CMastoclonella headi ) p. 244 [sep. p. 369]. 
t Dendroclonella rugosa , p. 252 [sep. p. 376]. 
Rauff, t. c. gives full descriptions of the following species : — 
t Aulocopium aurantium , Oswald, p. 257 [sep. p. 381] ; A. cylindraceum, 
Roemer, p. 267 [sep. p. 391]. 
i Aulocopella cepa , Roemer, p. 268 [sep. p. 392]. 
