Sponges from the Atlantic Ocean. 397 



from station 82 = 312 fathoms, and the latter from G5 = 345 

 fathoms. 



Although Poi/i).'ipon(/ia Lovenii i.s furnished with a ion? 

 stem like CometeUa^ and Latritnculia cratcra is laminiform 

 incrusting, there is so little difference between the shape and 

 disposition of their spicules, that I cannot help thinkiu'^ that 

 both ou,L,dit to have been put undr'r the same ijeneric name. 



Again, while Schmidt places his genus Cometella among 

 his Suberitidinre, he places LatruncuUa cratera under his 

 Dcsmacidinie. But if Podospoyigia and LatruncuUa be but 

 species of the same genus, as I have above assumed, and tlie 

 structure of Cortiete/fa, especially C. sfel/ata, 8dt., be closely- 

 allied to that of Podospongia Lovenii {\\\\\c\\ is the case), then 

 it ai)j)ears to me that all these should come under the Suberites 

 where Schmidt has placed hisCometella, if not Schmidt's lami- 

 niform SceptreUa regalis also, whose body- or linear spicule 

 according to the type specimen in the British Museum, is like 

 that of the rest, viz. acuate, smooth, fusiform, while the 

 sceptre-like flesh-spieule only differs from that of LatruncuUa 

 in the presence of spines over its rays and of three forms of the 

 anchorate, which ''forms," as Schmidt has observed (Atlant. 

 Spongicnf. p. 58), are certainly very remarkable; but still they 

 are but flesh-spicules, the value of which in s}>ecific distinction 

 is, as 1 have before stated, not always of much consequence. 



Geodia nodastrella, n. sp. (PI. XVI. fig. 45.) 



General form irregularly tuberous (like a potato) when large, 

 spheroidal when small ; free or fixed, presenting one or more 

 points of attachment according to the circumstances and situa- 

 tion under which it has grown, witli here and there large, 

 deep depressions of the surface. Colour yellowish opaque 

 white. Surface even, presenting here and there the deep 

 depressions mentioned, bottomed by a cribriform stiiicture. 

 Dermis consisting of a reticulated layer of sarcode charged 

 with minute nodastrelloids (PI. XVI. fig. 45,//, k) ; stelliferous 

 in api)earance, on account of the interstices being most deve- 

 loped in j)atclK'S linked together by the general reticulation: 

 supported on bundles of small, dermal, acerate spicules that 

 project from the subjacent petrous crust (fig. 45, //), which con- 

 sists of an agglomeration of siliceous balls, held together by 

 sarcode charged with nodastrelloids, and pierced by numerous 

 holes (which respectively are overlaid with the stelliform patches 

 of the dermal reticulation iust mentioned) opening internally 

 into the great marginal cavities of the pore-system. Pores 

 consisting of the interstices of the dermal reticulation, opening 



