REPORT ON THE HEXACTINELLIDA. 273 



the literature of the group something about tliis Farrea tubulata, which, so far as I am 

 aware, is referred to only in this place. 



As to the irregular network of beams with central canals of various widths, which 

 adhered to the inner side of a Farrea gassioti, Bowerbank, and which is spoken of by 

 Bowerbank as Farrea parasitica, one can scarcely say more than that it belonged to a 

 Hexactinellid, for the fact of its connection with the genus Farrea is not even plausible 

 from Bowerbauk's own description and figure. 



The Farrea valida of Bowerbank was established upon a small fragment of a 

 reticulated skeleton. The fragment, which is regarded by Bowerbank as representing 

 the dermal skeleton, is distinguished by the possession of uniform square meshes, by 

 thick, smooth, tubular beams in the network, and by short, tuberculated, conical teeth 

 and prickles. This dermal skeleton is associated with an inner body skeleton formed of 

 distinctly thinner, smooth beams, but of this skeleton little is preserved. The numerous 

 hexradiate crowded spicules, which are placed upon, and have one ray at right angles to 

 the beams of the framework, are noteworthy. 



Bowerbank designates by the name of Farrea spinosissima a fragment of a skeleton, 

 consisting of several reticulated layers, and provided with more or less square meshes. 

 From the tubular beams, which are of various thickness, though generally slender, 

 numerous long pointed prickles project at right angles, and are either smooth or slightly 

 beset with spines. 



Farrea spinifera was erected by Bowerbank on the basis of a skeletal fragment, 

 whose beams, which are of various thickness and provided with a central canal, surround 

 more or less regular meshes, and are distinguished by long, transversely disposed, or 

 slightly conical prickles. 



A small skeletal fragment, which Bowerbank has named Farrea spinulenta, differs 

 from most of the others hitherto referred to in the very convenient circumstance, that in 

 the present case a portion of the soft tissues, along with the free spicules that occurred 

 in them, was preserved in the dried specimen. It is true that here also it is not quite 

 certain whether the dried mass in question really belonged to the same sponge as the 

 siliceous skeleton, but it is in the highest degree probable. The framework consists 

 of a simple network with square meshes and long rough teeth, which project on both 

 sides at right angles to the knots of the network. 



As was to be expected, Bowerbank failed to find any central canals in the beams 

 of the siliceous network of this fragment, which was certainly taken from the sea bottom 

 in a living condition. The skeleton was not yet macerated and dissolved internally 

 like the majority of the other specimens of various species of his genus Farrea, which 

 have been referred to above. These apparently solid beams of the network are, however, 

 not quite smooth, but are beset with small pointed tubercles or with parallel longitudinal 

 rows of fine prickles, which stand at equal distances from, and alternate with one 



(ZOOI. CHALL. EXP. — PAKT LIU. — 1887.) Ggg 35 



