268 PROCEEDINGS OF THE NATIONAL MUSEVM. vol.xxiv. 
giu'i'eii.rll described hy Grote and Pitt^ from the Wat^rliiue near 
Buffalo, New York. 
The examination of specimens of tliis species in the collections of 
the U. S. National Museum shows it essentially to differ from B. 
newlhil o\\\\ l)y its more robust, linear, and more rarely forked divi- 
sions. The texture is of precisely the same character, thoug-h the 
filamentous ( ^) elements are less distinct. 
On account of the relatively large amount of carl)onaceous residue 
and the slightly rugose or vesicular texture, which is in strong con- 
trast to the delicate tilm, smooth impression, noncarbonaceous cast, or 
the coralline residue of most fossil algte, those forms with the charac- 
ters of the types in hand or of BHthotrepMs lesquereuxii are regarded 
by many paleontologists as probabl}' representing sponges. Neither 
of the specimens described above, which have been submitted to a num- 
ber of experts" in Paleozoic invertebrate paleontology, nor the exam- 
ples of the species last mentioned, appear to reveal a sponge structure 
or the normal occurrence of sponge spicules. The evidence in support 
of a sponge relationship for these organisms appears therefore to lie 
in their dense, apparently vesicular texture, and their occurrence in 
distinctly marine beds and in association with a marine fauna. 
It is not the purpose of the writer to strenuously urge that these 
fossils are marine alga?, although he believes them to be such. The 
evidence, or perhaps to speak more accurately, the circumstances 
which point toward a place for these types among the marine alga? are: 
(«) The marine habitat; (/>) the typically algoid form of development 
and growth, and (c) the aspect of the residue. All of these features may 
pertain to a fossil sponge; yet the absence of a regular sponge struc- 
ture, and especiallj" the lack of spicules in these well-preserved speci- 
mens, argues somewhat strongly against a reference to a sponge group. 
Without such characters these fossils can not safely be referred to that 
class of organisms. On the other hand, the reference of the forms 
from the Waterlime to the alga? can not be conclusively demonstrated, 
since neither the histology nor the fructification is known. Evidence 
of this class, though most important, is, however, Avanting in most of 
the fossil types whose thalassophytic nature is generally admitted, 
although the innnediate systematic classification of the latter is usually 
artificial and largel}" conjectural. 
There are many types of living algse representing various genera 
and even families with which the Bufhotreph/K group may with interest 
be compared. One of these which, in the judgment of the writer. 
iBull. Buffalo Boe. Nat. Hist., Ill, 1876, p. 88. 
2 The thanks of the writer are due to Mr. Charles Schuchert, of the U. S. National 
Museum, and Mr. E. 0. Ulrich and Dr. George H. Girty, of the IT. S. Geological 
Survey, for their courtesy in examining the fossils from Kokonio with a view to the 
detei'tion of sponge characters. 
