Si/noim6 of the Australian Galcarei, Heterocoela. (So 



pointed ; rti)ical ray very strongly developed, gradually 

 thickening tor about two-thirds of its length, wliere 

 it is extraordinarily stout, then bending shaiply and 

 tapering more suddenly to a sharp ])oint, length about 

 O'loo mm., greatest tliickness up to ()()28 mm. though 

 generally less. (2) Gastral triradiates ; sagittal or suli- 

 regular, with long, slender, gradually sharj)-pointed rays, 

 the oi-al rays often somewLat curved. (3) Subgastral 

 sagittiil triradiates, not clearh^ differentiated from tlie 

 ordinaiy tubar spicules. (4) Tubar triradiates ; with very 

 long, straight, slender, conical basal ray and shorter, widely 

 ■extended, often slightly curved oiul rays. In spicules 

 taken from about the middle of the length of the chamber 

 the basal ray measures about 0"17 by ()-07 mm., and the 

 -orals about ()-l by 0'07 mm. ; but there is a good deal of 

 variation. In some of the tubar spicules a fairly well 

 developed apical ray is found. In some of the most distal 

 triradiates the basal ray, now much shortened, is curved 

 outAvards so as to lie in tlie pore-bearing membrane, 

 which is also supported b\- small, scattered tiiradiates and 

 oxeotes like those found at the distal ends of the chambeis. 

 {5) Oxea of the distal ccmes ; short but i'airly stout, more 

 or less club-shaped, usually with the thick distal portion 

 bent at an angle to the remainder; measuiing about 0()<S 

 by 0-008 mm. ; these characteiistie little spicules are 

 arranged in dense tufts at the distal ends of the chambers. 

 Locality.— ^e-Av Port Phillip Heads (coll. J. B. Wilson). 



13. Si/con (jcldinosum, Blainville, sp. 



Alcijojicelluriif/elatino.sinn, Blainville. Actinologie, p. 52!.). 



Sycandra alcyoncellum, Hjeckel. Die Kalkschwamme. 

 Vol. 2, p. 333. 



Sycandra arhorca, Ha^ckel. Die Kalkschv/anime, Vol. 2. 

 p. 331. 



This common Australian species is veiy variable in foi'uj, 

 being eithei- colonial (generally richly blanched) or solitary, 

 with the oscula sometiiues naked and sometimes provided 

 with a fringe of .spicules. The shape of the dermal oxea also 

 varies greatly, from club- or nail-shaped to sharply-pointe'd 

 at each end. The extensive series of specimens in my col- 

 lection, from various parts of Australia, shows that it is quite 

 impossible to separate Hiieckel's two species, arborea and 

 alcyoncellwni, from one another, and I revert to Blainvilie's 

 ■original name, gelatinosuni, for both. 



C4 2 



