with some Remarks on the Nature of the Spongiæ Marine. 397 
thin, diaphanous, and colourless filaments, to spring from the surface of the 
Spongilla fluviatilis, when kept even in fresh water, and to increase in length. 
This latter fact I consider as the better accounting for the presence of those 
filaments; and I entertain in my own mind little, if any, doubt that the fila- 
ments of the Conferva (or Oscillatoria probably) which I have so repeatedly 
examined under the microscope, and seen attached so often to that Sponge, 
are in reality the * filamens flagelliformes” spoken of by Dujardin, and that 
the motions of that Conferva or Oscillatoria in the liquid, easily and most na- 
turally explain the cause of *les filamens agités sur le contour de certains 
fragmens” of the Spongilla lacustris. Wherefore I think no analogy can be 
drawn from these filaments, as this author has done in the following passage, 
De ces parcelles le plus extérieures sont, en outre, munies de longs filamens 
flagelliformes, comme les Monades, les Gonium, les Volvox, &c. pour déter- 
miner à la surface le déplacement de l'eau et par suite les courans daus les 
oscules, d’où résulte un contact plus multiplié de la partie vivante avec le 
liquide, qui lui fournit des matériaux dassimilation*,” with the organs of 
motion of those Znfusoria; because the former do not at all resemble, as far as 
I can learn from the researches of Dr. Ehrenberg, the latter, which are only 
cilia or mere set, and not what could with any propriety be termed * very 
long, whiplike filaments, of an extreme slenderness." 
And in the third place, I cannot from M. Dujardin's observations under- 
stand that the * parcelles amorphes," by a grouping or aggregation of which 
he supposes the mass of the Sponge itself to be formed, are in any respect 
more “analogues aux 4mibes,"—*which Amæbæ, Ehrenberg tells us, are or- 
ganized animalcula, possessing at least a mouth and gastric sacs,—than are 
similar portions of many of the gelatinous structures of the Algæ, or even of 
certain kinds of the Fungi. 
Moreover, it is clear that no good argument in support of the animality of 
the Spongillæ can be brought forward from their smell; for I have found this, 
when the specimen is quite fresh and immersed in pure water, to be rather 
pleasant than otherwise, but on the decay of the gelatinous portion it cer- 
tainly is powerful and offensive; though I am sure that very much of its 
disagreeableness arises from the death and putrescence of some parasitical 
See Annales des Sciences Naturelles, Seconde Série (Zoologie), tom. x. p. 10. 
