REPORT ON THE HEXACTINELLIDA, 113 



Family II. Asconematid^. 



Lyssacina of sack-, tube-, beaker-, or mushroom-like form, fixed either directly or by 

 means of a round stalk. The body-wall, which is not perforated, forms a thin soft plate 

 or a compact mass, which represents either the thick wall of a beaker, or the arched 

 plate of a mushroom-like body. In the latter case the gastral surface has become the 

 convex outer side. 



Both dermal and gastral surfaces are densely and uniformly beset with hexact and 

 pentact piauli, in which the freely projecting fir-tree-like ray is prominently developed, 

 while the parenchymal ray is usually small or entirely atrophied. The four transverse 

 rays, which are cruciately disposed, lie embedded in the bounding skin, and the whole 

 spicules are accordingly designated autodermalia and autogastralia. Below these pentact 

 hypodermalia and hypogastralia occur. 



The rosettes which lie scattered between the diact or hexact principalia are for the 

 most part discohexasters. 



Subfamily 1. Asconematin^. 

 Sessile sack-, cup-, or tube-like Asconematidse, with a thin, flabby, pliable wall. 



Genus 1. Asconema, Saville Kent. 



1870. S. Kent, Monthly jMicr. Journ., Nov., p. 241 (Asiwiema setuhalense). 



1871. Gwyn Jeffrey.s, Proc. Roy. Inst., N. 54, p. 258. 



1872. Gray, Ann. and Mag. Nat. Hist., vol. ix. p. 442. 



1873. Thomson, Depths of the Sea, p. 429. 



1874. Carter, Ann. and Mag. Nat. Hist., vol. xii. p. 349. 

 187,4. Gray, Ann. and Mag. Nat. Hist., vol. xiii. p. 284. 



1875. Marshall, Zeitschr. f. wiss. Zool., Bd. xxv., Suppl., p. 142. 



1876. Marshall, Zeitschr. f. wiss. Zool., Bd. xxvii. p. 113. 

 1880. Norman, Ann. and Mag. Nat. Hist., voL vi. p. 430. 



1880. 0. Schmidt, Spongien des Meerbusens von Mexico, ii. p. G5. 



1881. Milne-Edwards, Comptes rendus, xciii. p. 876. 

 1885. Filhol, La vie au fond des mers, p. 288. 



History. — Among the marine Sponges preserved in the Lisbon Mu.seum of Natural 

 History, Saville Kent detected in 1870,^ on the occasion of the " Noma " expedition, some 

 large, but only partially preserved cup- or sack-shaped specimens of " felt-like consistence, 

 composed of an interlacement of long filiform siliceous fibres or spicules, and, interspersed 

 among these, hexradiate spicula of various sizes and minute multiradiate ones with 

 capitate extremities." For these specimens he erected a special genus, Asconema, and 

 characterised the single representative species, Asconema setuhalense, in the following 



1 Monthly Micr. Journ., p. 245, 1870. 

 (zool. ch.\ll. EXP. —part liii. — 1886.) Ggg 15 



