16 THE VOYAGE OF H.M.S. CHALLENGER. 



slight ; a more noteworthy one lies in the arrangement of the spicules, for in our 

 variety the primary fibres are well marked oif from the secondary ones, and contain 

 more than one row of spicules, usually about two or three. We cannot, therefore, say 

 of our sponge, as Schmidt does of his types of the species, " Die doppelspitzigen Nadeln 

 bUden das charakteristische einreihige Netzwerk der achten Renieren." There is not, 

 however, by any means sufficient diflference to justify the erection of a new species. 

 As no one has ever figured this interesting form, we take the present opportunity of 

 doing so ; no one besides Schmidt seems hitherto to have met with it. 



Locality. — Station 75, Ji;ly 2, 1873 ; lat. 38° 38' N., long. 28° 28' 30" W.; ofi" the 

 Azores ; depth, 450 fathoms ; bottom, volcanic mud. About a dozen specimens. 



Habitat. — Adriatic Sea (Schmidt) ; off the Azores (Challenger). 



Reniera aqu^dvctus, Schmidt, var. infundihularis, nov. (PI. I. fig. 2 ; PI. II. 

 fig. 8). 



1862. Reniera aquxdudus, Sclimidt, Spong. Adriat. Meeres, p. 73, pi. vii. figs. 6, 6a, 66. 

 1884. Reniera sp., Eidley, Zool. Coll. H.M.S. " Alert," Brit. Mus., p. 410. 



Sponge (PI. I. fig. 2) consisting of a thin lamella, folded so as to form irregular 

 funnels and tubes which may anastomose. The largest specimen is a complex, hollow, 

 thin-walled mass growing together with a Gorgonia ; the shape of the whole is very 

 irregular, and its greatest length is about 100 mm. The wall of the sponge is only 

 about 2 mm. thick. Colour in spirit pale yeUow. Texture very delicate, spongy and 

 fragile. Sm-face uneven but smooth. Dermal memhixine very thin and transparent, 

 allowing the round or oval subdermal cavities to show through, and thus giving to the 

 surface a beautiful reticulate appearance. 



Skeleton. — Typically Renierid in arrangement, i.e., forming a rectangular, unispicular 

 reticulation. 



Spicules. — Small, smooth, very slightly curved oxea (PI. II. fig. 8), rather slender 

 and sharply pointed at each end; size about 0"17 by 0'008 mm. 



This variety differs from the types of the species mainly in external form ; forming 

 funnel-shaped or only irregularly tubular masses instead of regular cylindrical tubes. 



Th& -namQ infundihularis w^^ suggested by Ridley ^ in 1884 for some fragments 

 of a Reniera obtained by the " Alert " in Torres Strait, which may probably be included 

 under this species, and which also differ from the types in not forming definite sym- 

 metrical tubes ; this sponge agrees so closely in spiculation and external form (though, 

 from the fact that fragments only were obtained, we cannot say certainly that it was 

 infundibular) with the Challenger variety, that it seems desirable to include both under 

 the same name. 



1 Zool. Coll. H.M.S. "Alert," Brit. Mus., p. 411, 1884. 



