246 Mr. H. J. Carter on Deep-sea 



with none of the surface left, it fails to afford its general form. 

 The unconnected brown fragment is in company with speci- 

 mens of Tisiphonia agariciformis only ; while that on the shell 

 has with it Tisiphonia, Hymedesmia Joknstoni, Bk., Hyme- 

 desmia verticillata, Bk., and Desmacella pumilio } Sdt., also 

 a branched Suberite with pin-like spicule only, Tethya 

 cranium, and Halichondria ventilabrum. 



In the brown fragment there is no tricurvate (fig. 28) ; but 

 it is abundant in the fragment growing over the shell. I also 

 observe that, in the figure of Hymedesmia Joknstoni given by 

 Dr. Bowerbank (B. S. vol. i. pi. 18. fig. 293) from a 

 Madeira specimen, there is no tricurvate, while the tricurvate 

 is a prominent object in a specimen of the same sponge from 

 Madeira in the British Museum. Still as it was the habit of 

 Halichondria abyssi to take in grains of sand and foreign 

 spicules into its structure, I am still doubtful, as the tricurvate 

 is not in both specimens, whether it also may not have belonged 

 to a different sponge. 



Thus we have here another or third sponge whose anchorates 

 have the clam-shaped or umbrella-like ends similar to those of 

 Cladorhiza and Chondrocladia, while there are three forms of 

 skeleton-spicules instead of one, hence resembling, but for the 

 absence of spines, some of the varieties of Halichondria 

 incrustans ; so that, unless these clam-shaped ends are to be 

 considered the chief grouping characters, the presence of the 

 three forms of skeleton-spicule, together with the massive 

 areolar structure, the sessile incrusting habit, and the " crumb- 

 of-bread "-like structural appearance of this sponge, must ally 

 it more to H. incrustans than to Cladorhiza or Chondrocladia } 

 where the general form is branched stem-like, and there is 

 only one form of spicule, like that of Esperia. 



Lastly, I would observe that there is in both specimens a 

 minute equianchorate spicule (fig. 27, c), about 4-6000ths inch 

 long, in great abundance, which, although with straight shaft 

 and anchor-like head, seems to me to be no more than the 

 embryonic form of the great equianchorate flesh-spicule with 

 bent shaft and deeply dentate clam-shaped heads. 



Halichondria for cipis, Bk. PI. XIV. figs. 29-32, and 

 PI. XV. fig. 41, a, b. 



General form massive, lobed, sessile, stiff, areolar, like 

 " crumb of bread." Sessile. Colour light grey (PL XIV. 

 fig. 29). Surface irregularly areolar, owing to the form of the 

 subjacent skeleton-structure ; covered with a dermal sarcode, 

 Avhich, adhering to the projecting points of the former, pre- 



