514 HYATT'S REVISION OF THE 



Variety exotica (PL xvi, fig. 13). Differs from the preceding merely in its long fistular 

 orifices closely approximated, or nearly completely separated. 



Loc, Nassau, in Soc. Coll. 



Variety soUda (PI. xvi, fig. 10). This is part of a larger specimen preserved in Ward's 

 Museum, Rochester, N. Y. The branches are solid, as in variety duplex, and also have the 

 cloacal apertures on the sides, but are palmate or flattened in form instead of rounded. The 

 surface is rather smoother than in most varieties, except rotunda. 



Spongia discus D. et M. 



Spongia discus Duch. et Mich., Op. cit., p. 37. 



The specimen figured (PL xv, fig. 3) so closely corresponds with the description given by 

 Duchaissing and Michellotti, especially with regard to the surface, that I have thought it 

 best to retain their name. If these authors had not given it a distinct name I should have 

 doubtfully referred it to sub-species tulndlfera as a variety, though I know of no variety 

 which presents so marked a departux'e from the type of its species in the aspect of the sur- 

 face. The comparison made by these authors between the surface of specimens dried with 

 the epidermis remaining and the channeled surface of worm-eaten wood, is remarkably 

 good, and it can be separated from sub-species tuhtdifera by the spinous look of the tufts 

 of primary fibres, and the greater stiffness and dark purplish color of the skeleton. 



Loc, Nassau, in Soc. Coll. 



Variety anomala. This curious form ajDpears to agree in all respects only with discus, 

 of which species it is certainly wisest to regard it as a variety. The colony is composed of 

 an irregular assemblage of fistulose sponge masses, extending in an irregular manner over 

 the corallum to which it is attached. The whole is about six inches long, three inches in 

 height at the deepest part, and about three inches thick. The central portion is made up 

 of a line of four or five large apertures elevated upon a sort of crest which appears to be 

 composed of a number of fistulose masses formerly sejDarate, but now welded together. 

 On the sides, and more or less intimately united with these, are two fistulose branches. 

 The color is purplish, as it is also in the dried specimen of the typical S^jongia discus just 

 described, and the locality is the same. The surface has not that worm eaten aspect which 

 distinguishes the surface of the tyj^ical form, but it approximates to that condition. That 

 is to say, it has larger secondary tufts of fibres than sub-species inbidifera, and otherwise 

 resembles Spongia discus in the generally rough irregular aspect of the surface. 



Loc, Nassau, in Soc. Coll.; Havana,, in Coll. Mus. Corap.. Zoology, and Bennuda, in CoU. 

 Acad. Nat. Sciences of Philadelphia. 



Notwithstanding these very distinct characteristics, I describe Spongia discus as a distinct 

 species with considerable doubt, feeling that it may, with more evidence, prove to be 

 merely a variety of tuhuUfera. This doubt has been much strengthened by the receipt of 

 another Bermuda form, a fragment of which was recently forwarded me by Mr. Goode. 

 This has an aspect more closely hke tidjidifera than any of the above, though the skel- 

 eton is still very dark colored and very coarse. 



Variety Nicholsoni. This variety is very similar in the aspect of the surface to the 

 typical form, but has a coarser fibre and stiffer skeleton when dried. The color of the skel- 

 eton varies considerably from a dark purplish brown to a very hght brown. The aspect of 

 this variety approximates remotely to Spongia graminea, and leads the observer to think 



