36 Dr. J. V. Barboza du Bocage on Hyalonema boreale. 
V.—On Hyalonema boreale. By J.V. Barsoza pu Bocace. 
To Dr. J. EB. Gray, F.RS. 
My pear FRIEND, Lisbon, May 6, 1868. 
I have just received the interesting memoir of M. Lovén 
upon Hyalonema boreale*. I must confess that M. Lovén’s 
publication has caused me some vexation, as more than two 
months ago I prepared a similar memoir, which I have been 
hitherto prevented from publishing by illness. Since the 
17th of February I have been in possession of two curious 
specimens of a Spongiad, which I immediately regarded as 
the young of Hyalonema lusitanicum. 
I find some important differences between my specimens and 
that described by Lovén. In the first place, the sponge which 
forms the head has no apparent osculwm; and then the sarcode 
is covered with very complicated spiny spicules, which are not 
noticed by Lovén. 
I do not share all Lovén’s ideas. I cannot admit that the 
sponge which accompanies several specimens of Hyalomena 
from Portugal and Japan is the sponge-head of the young 
specimens; on the contrary, I am persuaded that the sponge 
which persists in the adult specimens is precisely that which 
forms the dilatation of the base, so that it is the upper portion 
or extremity of the filaments which re- 
mains free. The followimg are my rea- 
sons :— 
1. T remarked in my two young speci- 
mens that the large spicules constituting 
the axis all terminate below at the same 
level, whilst their superior extremities re- 
main at different elevations. Now all the 
adult specimens present this same cha- 
racter: the filaments have their extremi- 
ties at the same level in the part enclosed 
in the sponge, whilst they show their free 
extremities at different heights. I think 
therefore that this sponge is inferior, and 
that it corresponds to the sponge which 
occurs at the base of the young specimens. 
(As a matter of course, I regard the speci- 
men figured by Lovén as a young Hyalo- 
nema.) : ; 
2. The following is another argument ice ie ae 
in favour of my opinion. I possess a very sane Pees 
_* [A translation of this memoir, with which we have been kindly fur- 
nished by the author, will appear in our next Number.—Ep. ] : 
