1907.] Records of the Indian Museum. 269 



II. — Gemmules of Trochospongilla philloUiana, mihi. 



In my original account of this species {Journ. Asiat. Soc. 

 Bengal, igoy, p. 22) I stated that the covering of the gemmule 

 was thin. An examination of numerous specimens has shown 

 me that this statement was incorrect as regards the majority of 

 examples, in which the coating of granular substance is thick 

 but unevenly distributed. Viewed from the external surface, the 

 gemmules appear to be covered with little pits. These coincide 

 with the position of the gemmule spicules and are in fact funnel- 

 shaped passages leading from the external surface of the gemmule 

 to the outer rotula of each spicule. So characteristic and so con- 

 stant does this feature appear to be that I am inclined to think 

 that in the type of the species the gemmules were not fully deve- 

 loped. In my description of these gemmules " cylindrical " is a 

 lapsus calami for spherical. 



III. — Embryos of Ephydatia blembingia, Evans. 



Dr. Richard Evans in his original description of this species 

 {Quart. Journ. Micr. Sci., 1901, p. 71) notices certain niinute 

 basket-shaped bodies lying in cavities in the sponge, and is in- 

 clined to regard them as examples of a parasitic species, 

 although their spicules only differ from those of the adult E. blem- 

 bingia in their small size. Dr. F. Harmer, of Cambridge, has 

 recently sent me one of Dr. Evans's specimens, and I have been 

 able, thanks to its excellent state of preservation, to examine these 

 bodies. They appear to me to be embryos in different stages of 

 development. The smallest consist of rounded masses of cells, 

 which in some cases can be seen to be of two sorts, a number of 

 smaller ones and several larger ones. The compressed form of the 

 larger examples is probably due, as Dr. Evans himself suggests, to 

 shrinkage in preservation. In their later stages the bodies lie m 

 well-defined cavities in the sponge, each body being surrounded 

 by a deUcate membrane secreted by a layer of flattened cells that 

 apparently belong to the parent sponge. The body itself consists 

 of an external layer of columnar cells and of an internal mass 

 containing a large cavity. The cavity is situated towards the 

 narrower end of the body and is enclosed at this end by a thm 

 layer of cells that mostly have a starlike outline. The main bulk 

 of the mass is belo v the cavity and consists of cells of several kinds, 

 amongst which may be distinguished spiculiferous cells bearmg 

 spicules that are smaller, as yet, than those of the adult sponge. 

 In short, an optical section of the body, apart from the membrane 

 in which it is enclosed, closely resembles the actual section of an 

 embryo of Spongilla lacusiris figured by Evans in fig. 9, plate 

 xxxvi, vol. xlii of the Quarterly Journal of Microscopical Sci- 

 ence, 1899. In his account ot Ephydatia blembingia he says that 

 he was unable to make out the exact structure of these bodies. 



