Dr. J. E. Gray on Hyalonema Schultzei. 373 



sing; for its diameter is often six times as large as the thick- 

 ness of the coating. Unfortmiately the only specimen known 

 has been much bleached, so that it is impossible to say 

 whether the almost total absence of all detached silice- 

 ous bodies may be looked on as a distinguishing character of 

 this genus. Judging from the structure of the tissue, this 

 sponge might perhaps be ranged in the same genus with 

 Farrea orca^ Bowerb. ; but as only fragments are known of 

 the latter, which possibly might belong to Euplectella cuciimer^ 

 Owen, in whose roots they were found, for the present Farrea 

 orca and Eurete simplicissimaj S.,must be considered different 

 species. A careful examination of the tissue of Euplectella 

 cucumer would settle the question. Detailed descriptions will 

 shortly appear in the ' Zeitschrift fur wissenschaftlicheZoologie.' 



XL VII. — Note on Hyalonema Schultzei, Semper, 

 By Dr. J. E. Gray, F.E.S. &c. 



After studying the translation of Dr. Semper's description of 

 Hyalonema Schultzei made for me by his wife, Frau Anna 

 Semper, to whom we are indebted for the beautiful figure of 

 the Philippine Holothuria^ and considering the additional in- 

 formation that Dr. Semper has most kindly communicated to 

 me personally during his stay in London, I have come to the 

 conclusion that it is very doubtful if Hyalonema Schultzei 

 really belongs to the genus to which Dr. Semper refers it, and 

 if it is not rather a true Sponge, a species of Euplectella^ or, 

 may be, of a new genus of sponges very nearly allied to Eu- 

 phctella. Unfortunately only a single specimen has as yet 

 been obtained, and it is without any polypes, if it ever had 

 any, which I doubt. It certainly differs in many most im- 

 portant particulars from what I have given in my paper in the 

 October Numxber of the ^ Annals ' as the character of the group 

 Hyalonemadse. 



The long spicules of H. Schultzei^ which have been com- 

 pared to the spicules of Hyalonema^ are like those of Euplec- 

 tella ; they have a cup-shaped knob or anchor at the tip, and 

 a series of recurved spines on the part near the tip, like those 

 figured by Owen (Linn. Trans, xxii. t. 21. f. 6 & 7.) These 

 spicules agree with those of both the species of Eujolectella 

 known, and are quite unlike those of Hyalonema^ which are 

 always imperfect at the end, without any anchor or projecting 

 spines, but with rings of small spines directed towards the 

 middle of the spicules, as described in my late paper. 



It is said that the upper ends of the long spicules of //. 



