Sponges from the Atlantic Ocean. 407 



22, ^) ; 2, the same but smaller, and for the most part centrally 

 inflated (fig. 22,7c), probably passing, when more developed, 

 into the former ; 3, stelliform, irregularly rayed, or with elon- 

 gated axis and rays chiefly developed at the ends bistellate- 

 like, rays linear (fig. 22, II). The large triradiate and sub- 

 quadriradiates, together with the acerate skeleton-spicules 

 which are very long, are confusedly arranged together through- 

 out the sponge, lying perhaps most horizontally on the surface, 

 while the flesh-spicules, imbedded in the sareode, make up the 

 rest of the mass, the larger microspined flesh-spicules being 

 chiefly confined to the interior, and the smaller ones to the 

 surface, while the stellates are dispersed generally and very 

 subordinate in number. Size of specimen about 1 inch long, 

 7-12ths inch broad, and 5-12ths inch in its vertical diameter. 



Hab. Marine, on hard bodies. 



Log. Atlantic Ocean, at station 24 = 292 fathoms, near Cape 

 St. Vincent. 



Obs. There is only one specimen of this sponge, which is 

 contained in a jar labelled " 24, 292 fathoms," which station 

 will be found on the chart accompanying the report of the 

 cruise of the 'Porcupine' in 1870 (Roy. Soc. Proc. no. 125). 

 It is accompanied by small specimens of several other 

 sponges, viz. Histoderma appendiculatuni, Hymedesmia John- 

 stoni, Oeodia, Tisiphonia^ TetJiya cranium, Pachastrella abyssi, 

 and a histodermal form of Halichondria panicea, together 

 with several rolled pieces of agglomerated spicules of various 

 sponges. 



There is a great resemblance between the spicules of this 

 sponge and those of Schmidt's Sphinctrella horrida, Atlant. 

 Spongienf. p. Q5, Taf. vi. figs. 6 & 7 (that is, rather, to the 

 spicules in the slide of this sponge belonging to the British 

 Museum), but it differs much from Schmidt's illustration fig. 7, 

 in which there are distinct sphinctral areas of tlie dermal sar- 

 eode charged with stellates, while the larger linear skeleton- 

 spicules are obtusely pointed — which is quite opposite to the 

 above description oi Pachastrella amygdaloides, taken, too, from 

 a specimen unusually perfect. 



Pachastrella geodioide^, n. sp. (PL XIV. fig. 23 &c.) 

 General form globular, a little wider at the base than at the 

 summit, sessile. Colour dark grey. Surface even, uniform, 

 slightly roughened by projecting spicules ; dermal sareode 

 charged confusedly with the spicules of the species mixed with 

 minute foreign organisms of various kinds, directly continuous 

 with the internal structure that is not corticate. Pores in the 

 dermal structure, more or less indistinct. Vents small, scat- 



