460 COLLECTIONS FROM MELANESIA. 



The general form, the large development of acuate spicules, and 

 the echination by the long acuate spicules ally the species more 

 closely to Raspailia (Dictyocylindrus) than to Echinodictyum; the 

 cylindrical form of tho spined spicule agrees with the latter genus ; 

 but the share taken by the acuate spicule in the formation of the 

 fibre is conclusive as to its belonging to Raspailia. 



Subgenus Syeingella, Schmidt. 



In the description, in the Spong.Kuste Algier., at p. 10, of a species 

 from Algiers, named by him Raspailia syringeUa, Prof. Schmidt says 

 that it diverges remarkably from the type of Raspailia, having but 

 one form of spicule (spinulate) and (in the case of one specimen) a 

 well-marked vent ; he does not definitely form a new genus to con- 

 tain it, but suggests that if the two characters referred to should, 

 with further material, prove constant, a genus should be formed 

 for the species, and named SyringeUa. Fresh material has now 

 appeared, from which I describe the two following species. Although 

 the spicular character of Schmidt's species is (essentially) reproduced 

 in them, that of the presence of a vent is not ; therefore, although I 

 consider the group for which Prof. Schmidt provisionally proposed 

 the name SyringeUa to be of subgeneric value, I do not feel justified 

 in separating it generically from Raspailia, The group may be 

 defined as differing from Raspailia in the absence of the spined 

 acuate spicule. In the following species the skeleton-spicule has 

 usually lost the head, which R. syringella retains well developed. 

 It is interesting to find this subgeneric type so widely distributed. 



88. Raspailia (SyringeUa) australiensis. 

 (Plate XLII. figs, m, m'.) 



Erect, unbranched, consisting of a single, slender, cylindrical 

 column, tapering very gradually from about two thirds of the 

 height to the base on the one hand and to the rounded free 

 extremity on the other ; diameter at base and summit about half 

 that of the thickest portion of the stem. Surface in spirit semi- 

 gelatinous in appearance under lens, and minutely pilose and velvet- 

 like ; it is corrugated by closely set, irregularly interrupted, longi- 

 tudinal ridges. The sponge is, as a whole, tough and elastic : the 

 corrugated superficial layer loose and fragile, its greatest thickness 

 about 1 millim. Colour in spirit dirty white. The stem is formed 

 by a dense flexible rod of a dull yellow colour and smooth surface. 

 Tents not perceptible to naked eye or lens. Skeleton of axis con- 

 sisting of a close network of tracts of skeleton-spicules, the tracts 

 mostly arranged longitudinally, and connected by smaller tracts set 

 at oblique angles to them (as in Axinella, Schmidt, but much closer 

 together) ; tracts often confluent, at most only '15 millim. apart ; no 

 soft substance is apparent uniting the spicules. Skeleton of cortical 

 soft layer consisting of fascicles of skeleton - spicules, radiating 



