134 Records of the Indian Musciiin [Vol. X, 



Type No. Z.E.V. ^¥-' Ind. Mus. 



This sponge is closely allied to Mycale aegagropila. The size 

 and proportions of the spicules are, however, different; the skele- 

 ton, at any rate in the central parts of the sponge, is much 

 denser, and the complete absence of toxa, substantiated by an 

 examination of many fragments mounted whole as well as by 

 preparations of cleaned spicules, is apparently a distinctive 

 character, 



Gemmules closely resembling those of M. aegagropila as 

 figured by Vosmaer and Pekelharing {op. cit., p. 30, pi. i, fig. 3) 

 occur in specimens collected in October, 



Mycale madraspatana, sp. nov, 

 (Plates X, fig. 3 and xi, fig. 4.) 



In the structure of its soft parts, in dimensions and in the 

 form of its spicules this species closely resembles M. aegagropila, 

 but the chelae are arranged in rosettes and the skeleton is much 

 more highly organized : the colour in life is that of M. mytilorum. 



Skeleton. —Two distinct kinds of spicule-fibres can be recog- 

 nized. On the external surface, partly in the dermal membrane 

 and partly in the parenchyma immediately below it, run 

 comparatively^ stout, sinuous, non-anastomosing fibres, which 

 cross one another occasionally but branch sparingly and do not 

 fuse together. They are a little splayed out and occasionally 

 fork at both extremities, but form regular brushes at neither ; in 

 optical section as many as 12 spicules abreast can sometimes be 

 detected. These broad fibres are best developed round the oscula. 

 In the lower part of the parenchyma thinner fibres, 2 (or even 

 i) to 7 spicules abreast in optical section form a regular horizontal 

 network, branching freely and anastomosing, Transitionary 

 forms between the two kinds of fibres occur very sparingly. In 

 addition to the fibres there are many macroscleres scattered 

 horizontally in the parenchyma. These are not shown in figure 4, 

 pi. xi. 



Spicules: Macroscleres. — The majority of the macroscleres 

 closely resemble those of M. aegagropila except that the shaft 

 tapers more distinctly towards the blunt extremity; the heads, if 

 they can be distinguished, are narrowly oval. Together with 

 macroscleres of this type ver}' much more slender styli of approxi- 

 mately the same length occur sparingly. The average length of 

 the typical macroscleres is 0*279 mm., the extremes being 0*265 

 and 0296 mm. 



Microscleres. — Anisochelae, sigmata and toxa are found. The 

 anisochelae are arranged in rosettes, but the size and regularity of 

 these groups varies, together with the number of anisochelae present 

 in the sponge, in different specimens from the same locality. The 

 form of the spicule closely resembles that of the spicule of the same 

 type in M. aegagropila, but there are certain differences (best shown 



