REPORT ON THE HEXACTINELLIDA. ' 275 



1875 and 1876, we can obtain only in four cases any adequate conception of their 

 form; namely, on the one hand, in the case of Farrea gassloti and the very closely 

 related Farrea 2)0cillum, both of which have the same cup-like form ; and on the other 

 hand, in the case of Farrea Jistulata and Farrea lievis both of which are tubuliform 

 and are also closely related to one another. Which of the other ten species belong 

 to the one or the other of these two groups of forms, or perhaps to neither, it is 

 scarcely possible to say on account of the small size and imperfect condition of the 

 fragments examined. According to Bowerbank's own representation his Farrea 

 spinulenta seems to agree for the most part with the old Farrea occa, Bowerbank, so far 

 as regards the lattice-like framework. If this agreement were indeed more intimate 

 it would be of great importance for the establishment of the generic character of 

 Farrea, because some free siliceous spicules were found and described by Bowerbank 

 in the dried soft parts, and these are absent in the other cases. We must regret that 

 Bowerbank has communicated no definite information in regard to the free spicules 

 which he mentions as having been found in "various forms" in an original fragment of 

 his Farrea occa (and indeed in the so-called dermal skeleton); he only says (page 561) 

 that in Farrea spinulenta one may find that "the large simple rectangulate sexradiate 

 interstitial spicula with spinous radii, a few of which are entangled in the inner surface 

 of the dermal rete, also form efficient specific characters, none such having hitherto been 

 found in Farrea occa." 



In his description of the sponges of the Gulf of Mexico — 1880 — Oscar Schmidt 

 maintains his previous diagnosis of the sjDccies Farrea facunda. To the spicules 

 then described as characteristic he adds a hexradiate form in which every individual ray 

 divides at the extremity into from two to four (usually three) fine bristle-like teeth, 

 and he conjectures that in the previously examined specimens certain spicules represented 

 on his pi. V. fig. 9, which bear on each of their thickened extremities four transversely 

 arranged and somewhat recurved hooks, might be present as well as in the specimens 

 subsequently studied. He further reports that in the majority of his numerous specimens 

 those peculiar broom forms (Besengabeln) figured on pL i. figs 18, 19,' and in some the 

 umbelled spicules represented in fig. 2 of the same plate, were not to be found. He is, 

 however, by no means inclined to erect a specific difference on that account, and that 

 the less since the familiar fir-tree-like spicules occurred here and .there instead of the 

 absent " brooms." Only one form — in which the absent umbel and hook spicules are 

 represented by the so-called knob- broom form, that is to say, by forks with several teeth 

 which do not run out to points but terminate in terminal knobs, and which were in the 

 meantime described by Carter as Eurete farreopsis — should be excluded from his Farrea 

 facunda, and at any rate become the representative of a special species. On the other 

 hand, the genera Eurete and Aulodictyon, which were placed near Farrea hj Semper 



' Spongien des atlantischen Gebietes, 1870. 



