258 Contributions to ow Knowledge of the Spongida. 
demarcation in nature. But until all such facts as I have 
mentioned are known and duly considered, the classifica- 
tion of the Spongida will not become satisfactorily useful, 
although much may and must be done in this way previous 
to arriving even at this point; while at last, the nearest 
approach to the imaginary line of demarcation can only be 
attained by the most masterly mind on the subject. 
CELLULOPHANA, Sdt., 1862. 
Before concluding, it is desirable to turn our attention for 
a few moments to the nature of Cellulophana pileata, first 
named, described, and figured by Schmidt, who placed it 
among his Gumminez or Kautschukschwiimme (caoutchouc 
sponges), equal to our Carnosa (No. 4, p. 41, Taf. ii. figs. 24 
and 24a), but was so uncertain about its sponge-nature, that 
he proposed to refer the question to the botanists. He recurs 
to the subject again in his 2nd Supplement (No. 7, p. 22), 
but with little advancement, and finally ends with the de- 
scription of another species trom the coast of Florida, which 
isnamed C. collectrix, but, after all, adds in a “ footnote ” that 
the subject requires further observation (No. 13, p. 25). 
His illustration of Cellulophana pileata (0. c.) represents a 
vertical section of the entire body, which had a roundish form, 
elongated and enlarged upwards, about 8 inch high and 7 
inch thick, said to be “ etwas vergréssert,”’ whatever that may 
amount to, and to have been surrounded by a cortex enclosing 
a parenchyma, the former brown and ‘thick, according to the 
illustration, and the latter earmine, passing into grey inwards. 
In fig. 24a the epidermis. is. shown to consist of a thin fibrous 
layer with polygonal plant-like cell-structure underneath ; 
while the second species, viz. C. collectrix, contained foreign 
bodies. 
Now the chief objections to the sponge-nature of this 
organism are that no pores or oscula have been discovered in 
the epidermis, nor is there any excretory canal-system, while 
the presence of the polygonal cell-structure to which I have 
alluded (J. c. fig. 24 a) is also totally opposed, so far as my 
experience goes, to ordinary sponge-character, where all the 
cell-structure, if not polymorphic, 1s,.too gelatinous to present 
a defined cell-wall like that of plants. But J must refer 
the reader to the whole of Schmidt's observations, as they 
tend towards establishing the sponge-nature of this organ- 
ism; meanwhile I would mention that I myself labour 
under similar difficulties with the organism from the Gulf of 
Manaar that I have provisionally named Halsarca rubitingens 
