SPONGIARIA 



77 



L. taylori Lambe. Sponge small, solitary, globose, 6 mm. high and 

 4.5 mm. thick, with thick walls and a narrow cloacal cavity; spicules 

 triradiate, with long monaxials protecting the osculum: Vancouver 

 Island. 



FAMILY 3. AMPHOEISCIDAE. 



Conspicuous subdermal quadriradiate spicules with elongated in- 

 wardly directed rays: 5 genera. 



AMPHORISCTJS Haeckel. Cortex thin; spicules triradial and quadri- 

 radial: several species. 



A. thompsoni Lambe. Gulf of St. Lawrence. 



CLASS 2. HEXACTINELLIDA.* (TRIAXONIA.) 



Glass sponges. Sponges with usually rather thin walls and a large 

 cloacal cavity giving them a more or less tubular or basket-like shape; 

 spicules silicious, consisting of 3 crossed axes making them either 6-rayed 

 or belonging to the 6-rayed type, and either soli- 

 tary or joined to form a continuous skeleton 

 which often has the appearance of spun glass; 

 cloacal cavity large and unusually more or less 

 cylindrical, usually with simple radial flagellate 

 chambers opening out from it, the wall of the 

 cloacal cavity, however, often folded and the 

 chambers branched: about 12 families. 



FAMILY 1. EUPLECTELLIDAE. 



Body elongate, usually curved or twisted; 

 spicules joined together forming a network; 

 upper end the larger with a terminal sieve-like 

 plate; lower end with usually a mass of long 

 silicious threads which fastens the animals in 

 the mud: several genera. 



EUPLECTELLA Owen (Fig. 137). With the characters of the family: 

 several species. 



E. suberea Wyville Thomson. Body a straight, cylindrical, slightly 

 swollen tube, 25 cm. long and 5 cm. in diameter: West Indies, in deep 

 water. 



FAMILY 2. HYALONEMATIDAE. 



Body globose, elongate or cup-shaped with a long stalk composed of 

 long twisted silicious strands; several genera. 



HYALONEMA Gray. Body funnel or cup-shaped: several species. 



* See "Report on the Hexactinellida," by F. E. Schulze, Chall. Rep., Vol. 21, 1887. 



Fig. 137Eupleotella 

 (from Weysse). 



