QUARTERLY CHRONICLE. 151 
invaluable service in deciding the rights of the discussion. 
D. J. E. Gray seeks to prove, in opposition to the opinion of 
many naturalists, that Hyalonemaiis not a sponge, as supposed, 
but the axis and product of a polype. In this he is strenu- 
ously opposed by Dr. Bowerbank, who maintains, from 
microscopic evidence, that Hyalonema is a sponge. Professor 
Brandt, of St. Petersburg, classifies Hyalonema with the 
polypes, and regards a sponge observed at the extremity of 
very many specimens as a parasite. Professor Max Schultze 
in this paper maintains that the “glassy ” part of the speci- 
mens is produced by the sponge, and that there is a parasitic 
polype, which is quite distinct, and that Hyalonema is 
properly, therefore, a sponge, which frequently has a coral 
parasitic on it. The structure of the glassy threads shows 
clearly that they are long sponge-spicules ; and on this point 
Dr. Bowerbank and Professor Schultze agree. Dr. Bower- 
bank, however, declares that there is no parasitic coral, but 
that what appears to be such is really a “ cloacal”’ system 
proper to the sponge. Professor Schultze’s observations are, 
however, quite decisive on this point, for he has floated out 
the polypes themselves from dried specimens, and with the 
microscope has detected nematophores in their tissue. He 
also adduces other cases in which particular sponges are 
always affected with particular parasitic polypes, and gives 
a brief account of the microscopic structure of the true 
Hyalonema, which is fully figured and detailed in his mono- 
graph, ‘ Die Hyalonemen, ein Beitrag zur Naturg. der Spon- 
gien, Bonn, 1860. There can be very little doubt but that 
the eminent German microscopist has set the question at 
rest. 
** On the Young Stages of a few Annelids,” by Alexander 
Agassiz.—We have not space now to notice this most inte- 
resting communication, of which a succeeding part is pro- 
mised. At some future time we may be able to review M. 
Agassiz’ observations ; meanwhile we commend them to the 
reader’s notice. 
Proceedings of the Botanical Congress.—“‘ On the Structure of 
the Seeds of the Solanaceae, &c.,” by Tuffen West, F.L.S. 
We have been favoured with a copy of this excellent paper 
by the author. He gives an interesting series of observations 
on the structure of the seed in Solanaceze, Atropacee, and 
Scrophulariacee, illustrated by two plates, and points out 
the affinities indicated between these members of a group of 
allied orders which are indicated by these structures. 
ITALY.—Mem. della R. Acad. di Torino.—* On the Struc- 
ture of the Skin in Stellio Caucasicus,” by Professor F. de 
