skeleton siliceo-fibrous, more or less symmetrically radial ; 

 radii short and stout on the outer surface, and somewhat 

 longer and thinner ou the inner surface of the skeleton^ 

 forming a series of hexagonal spaces, which are nearly all of 

 the same dimensions^ central umbo of the ray giving origin 

 on its inner siu'face, often on both surfaces, to a long spine. 

 These spines, generally long, sharp-pointed, sometimes knob- 

 headed. Spicules, acerate ; retentive verticillately spined ; 

 attenuated rectangulated hexradiate, and subfusifoimi cylin- 

 drical entirely spinous. Main tube closed by an irregular 

 siliceous network, which is deeply concave. Pores and 

 dermal system unknown. 



Habitat. — Cape de Verde Islands, in museum of Lisbon, 

 in British Museum, London, and in my own collection (Sept., 

 1868) also oif south-west coast of Ireland in deep water; 

 Professor Thomson, " Porcupine " Expedition, 1869. 



Dr. J. E. Gray established the genus Aphrocallistes in 1858 

 for a very beautiful sponge from Malacca (' Proc. Zool. Soc.,' 

 London, 1858, p. 115, PI. XI, Radiata), A. beatrix. Dr. 

 Bow^erbank having identified the Iphiteon panicea of Yalen- 

 cienne in the museum of the Jardin des Plantes, Paris, as be- 

 longing to the same genus as^. beatrix adopts Valenciennes's 

 name. As, however there were never any descriptive characters 

 of the genus Iphiteon published until 1869 (it was affixed 

 to the specimen in the Paris Museum in 1800), and was 

 described as Aphrocallistes in 1858, I have no hesitation 

 in assigning the priority to Dr. Gray's name and in adopt- 

 ing it for those sponges, with a siliceo-fibrous skeleton 

 in which the reticulations are symmetrical. It is true that 

 by an accident Dr. Gray described the genus as having cal- 

 careous instead of siliceous spicules — an error which he 

 afterAvards corrected. But this mistake could not for a 

 moment mislead when the rest of the diagnosis and the 

 beautiful figure by Mr. Ford were taken into account ; in- 

 deed, such a figure Avith a name attached would amount to a 

 publication. 



It is confessedly unsatisfactory to describe a sponge from 

 a dead and bleached specimen ; for if in any group of the 

 animal kingdom, surely here we require all the assistance 

 it is possible to have from an examination of all the structures 

 of the organism. It is, therefore, not Avithout an apology 

 that I publish the above beautiful form as a ncAv species. 

 When examining the very interesting collection at the 

 Museum of Lisbon in September, 1868, I discovered three 

 or four specimens of this sponge, which I immediately re- 

 garded as a new species of this genus. Professor Bocage, 



