Dr. J. E. Gray on the Glassijication of Sponges. 457 



The small cup-sliaped specimen figured in the Proc. Zool. 

 Soc. 1859, tab. 15, as M. azorica, has distinct conical vents 

 on the inner surface ; two much larger, circular, very sinuous 

 specimens, also from the Azores, have only very minute vents 

 on the upper surface ; and the large circular sinuous specimen 

 from Madeira, which is called M. Bowerhankii^ has no visible 

 vents on either surface : so I believe them to be only varieties, 

 Mr. Carter observes, one should recollect that sponges often 

 grow from the roofs of caves and rocks, dependent from 

 above ; and what appears, when the specimen is in a museum, 

 to be the upper is in reality the lower surface, and the surface 

 next the root is in reality the upper one. 



Fam. 6. Farreadae. 



Sponge expanded or tubular. Skeleton nearly regularly 

 reticulated, with four-sided openings. 



i^ar/*ea,Kent, Microsc. Journ. 1870 ; Sympagellay 0. Schmidts 



Fam. 7. Dactylocalycidse. 



Sponge massive or expanded or cup-shaped. Skeleton 

 more or less regularly reticulated, w4th angular openings di- 

 verging from the centre. 



Dactylocalyx^ Myliusia^ Kaliapsis (Bowk.), Discodermia 

 (Bocage ?) . 



Fam. 8. AphrocaUistidae. 



Sponge tubular ; tube closed with a netted lid or a rounded 

 end. Skeleton more or less regularly netted with angular 

 openings. 



Aphrocalltsfes, see Kent, Microsc. Journ. 1870. 



C The sponge fixed^ formed of fusiform spicules anchylosed 

 together hy siliceous coats. Hexaradiate spines in the 

 sarcode. 



Fam. 9. CorbitellidaB. 



Sponge tubular, attached, without any anchoring filaments at 

 the base. The walls formed of irregular network or bundles of 

 siliceous needle-shaped spicules loosely arranged in slieaves 

 intersecting each other, and united by sarcode ; spicules of 

 skeleton and sarcode hexaradiate, free from one another. 



Euplectellada3, sect. B, Gray, P. Z. S. 1867, p. 530. 



Corhitella and Heterotella, Gray, I. c. \ Ilabrodictyon^ "W". 

 Thomson. 



I formerly regarded this family as a peculiar section of 

 Ann. & Mag. Nat. Hist. Ser. 4. Vol.'i^. 31 



