58 Mr. H. J. Carter on Specimens 



nodules, sometimes in company with other sponges, and some- 

 times alone. 



Loc. Gulf of Manaar. 



Obs. The extreme beauty of the large spicule of this species 

 so attracted my attention while it made its appearance in more 

 or less plurality among the fragments of other sponges which 

 I had mounted, that I determined to look for it in situ, feeling 

 almost convinced that it was one of the Ecccelonida, but 

 which, like Thoosa socialis, could, from its minuteness, be only 

 sought successfully with the microscope. This was accom- 

 plished at last, but not until I had often relinquished the search 

 as hopeless ; and then the fragment was observed to consist of 

 several dilated globular portions of transparent sarcodic mem- 

 brane united together isthmically, and densely charged with 

 the spicules of the species on their inner surface, so that when 

 contracted in the dried state they gave the little massive 

 appearance above mentioned. It was also in company with a 

 minute fragment of Thoosa socialis; but from its form and 

 approach towards the surface-apertures of the excavation in 

 which it existed by little digital processes densely charged with 

 the spicules of the species at their extremities, like those of 

 Alectona Millari, there can be no doubt that this is a truly 

 excavating sponge, for whose genus I have proposed the name 

 of u Dotona" after another of the sea-nymphs, and " pul- 

 cliella" from its great beauty. The annulation, when 

 examined by alteration of the focus, so that both sides of the 

 spicule may be examined, is found to be formed, as above 

 stated, of a spiral ridge whose coils are so close together that 

 at first they resemble annulations (fig. 24, d). 



Alectona Higgini, n. sp. 

 (PI. V. fig. 25, a-c.) 



Lining excavated cavities in a Melobesian nodule, in the 

 form of a sarcodic membrane charged on the inner side with 

 the spicules of the species. Colour now that of dried sarcode — 

 that is, yellowish. Spicules of three forms, viz. : — 1, subcylin- 

 drical, slightly curved, round at the ends, sausage-like, divided 

 irregularly throughout the body into a number of annular de- 

 pressions and inflations, the latter of which are microspined, 

 and very variable in form and length, the shortest being the 

 thickest, 5 to 20 by H to 2|-6000ths (PI. V. fig. 25, a) • 

 2, fine, hair-like, acerate, tending to the form of a tricurvate, 

 12-6000ths long (fig. 25, b) ; 3, flesh-spicule, consisting of 

 a straight shaft interrupted towards the centre by eight or 

 more faintly capitate rays radiating circularly from separate 

 points a little nearer to each other than to the extremities of 



