300 On West-Indian and Acajndco Sponges. 



Peculiarity in the AncJiorate . 



The only uiKlescribecl species of Esperia that I liave ex- 

 amined, in which the inequianchorate possesses a decided 

 peciiliarily, is the following, viz. 



Ksperia Cunniugltanii^ n. sp. 



Massive, lobate, sessile. Colour now pale yellow. Sur- 

 face undulating, rugose ; dermal layer lace-like, formed of a 

 stout reticulated structure, composed of smooth spiculo-fibre, 

 underneath the interstices of which is a finer one of the same 

 kind, whose interstices in the fresh state are tympanized by 

 the dermal sarcode in which the pores are situated ; supported 

 internally by a rigid spiculo-fibrous skeleton, whose branches 

 become thicker towards the older and first-formed parts of the 

 structure, which is traversed by the branches of the excretory 

 canal-system that open here and there in large vents on the 

 surface. Spicules of five forms, viz. : — 1, skeletal, acuate, al- 

 most cylindrical, smooth, curved, abruptly sharp-pointed, 

 slightly constricted inside the head, or with the latter ellipti- 

 cally inflated, about 112 by 2-fJOOOths inch in its greatest 

 dimensions (Fl. XI. fig. 17, o, h) ; 2, fiesh-spicule, inequi- 

 anchorate, 10-20-6000ths inch long, head oblong, narrow, a 

 little longer than the rest of the body, anterior or petaloid arm 

 a little shorter than the lateral ones, which are somewhat 

 everted at the free end ,• anterior arm of the smaller or lower 

 end prolonged upwards into a pointed conical process (fig. 17, 

 c, g) ; 3, flesh-spicule, bihamate, very fine, back or shaft 

 straight, suddenly cinwed in opposite directions at the ends, 

 about 6-GOOOths inch long (fig. 17, c7, A) ; 4, fiesh-spicule, 

 simple, tricurvate, very small, bow-sha])ed, 10-6000ths inch 

 long (fig. 17, e) : 5, trichites in sheaf-shape bundles about 

 the same length (fig. 11 ^f). No. 1 is chiefly confined to tlie 

 dermal and skeletal structure ; 2 is sparsely present, chiefly 

 in the dermal layer, together with 3 and 4, which are ex- 

 tremely fine and scanty. Size of one of the largest of the 

 pieces, of which there are many, all belonging apparently to 

 the same specimen, which mitst therefore have been very large, 

 6 by 4 inches in its greatest diameter. 



Hah. Marine. 



Loc. Stanley Harbour, Falkland Islands, and Otter Island, 

 Patagonia. 



Obs. The "process" which is extended upwards from the 

 central or petaloid arm of the lower end of the inequiancho- 

 rate, and is a simple elongation of this tongue-like part (fig. 17, 

 g)j is the most distinguishing and striking character in this 



