N. Annandalk: Notes on Freahwatev Sponges. [Vol. II . 



abundant in the dermal membrane^ scarce in the substance of 

 the sponge. Gemmules spherical, somewhat variable in size, 

 with a single aperture, which is provided with a trumpet-shaped 

 foraminal tubule and is situated at one side of the gemmule in 

 its natural position ; the inner chitinous coat devoid of spi- 

 cules, closely covered by an outer coat composed of a darkly 

 coloured chitinoid substance, in which the gemmule spicules 

 are embedded, lying parallel or almost parallel to the inner 

 coat. The outer coat forms a kind of mantle by means of 

 the skirts of which the gemmule is fastened to the support of 

 the sponge and which is pierced by the foraminal tubule ; 



Fig. I. 



Figs, i and 2 

 fig. 2 = a gemmule, 



Fig. 2. 



-SpoHgillu indica : fig. i = gruup of gemmule spicules, x 240 ; 



70. 



gemmules distinct from one another ; gemmule spicules short, 

 stout, sausage-shaped, covered with minute, straight spines, 

 which are sometimes absent from the extremities. 



Average length of skeleton spicules . . o"2046 mm. 



breadth of skeleton spicules 

 length of flesh spicules 

 breadth of flesh spicules 

 length of gemmule spicules 

 breadth of gemmule spicules 



Spoiigilla lapidosa, .sp. nov. 



0"OI72 



0-0053 



0-044 



0*0079 



Allied to S. loricata, Weltner. 



vSponge encrusting, black or grey, extremel}' hard, its surface with 

 occasional groups of spicules projecting ; dermal membrane 

 adhering closely to the surface ; oscula very small, sometimes 

 conspicuously elevated. vSkeleton incoherent, broad groups of 

 spicules arranged vertically occurring irregularly but being 

 devoid of any binding substance and only traversing a small 

 part of the thickness of the sponge ; transverse fibres absent ; 

 in the inferior part of the sponge the direction of a large pro- 

 portion of the spicules is horizontal, the number arranged 

 vertically being greater in the upper part. Skeleton spicules 

 sausage-shaped, sometimes slightly swollen at the ends, as a 



