488 Miscellaneous. 
On the Brain of Kunice Harassii and its Relations with the 
Hypodermis. By M. E. Jourpay. 
Quatrefages and Claparéde were the first to indicate the relations 
that exist between the hypodermic cellular layer and the nervous 
centres in some Annelides. More recently Ehlers, with reference 
to the brain of the species which is the subject of the present note, 
and Spengel, in his memoir upon a EKunician, Oligognathus Bonel- 
liv, have pointed out the difficulty of separating the brain from the 
hypodermis in the cephalic lobe of these worms. These notions, so 
contrary to the classical data and figures relating to the brain of most 
Annelides, seemed to us to need confirmation. With this view we 
have made sections of the whole of the cephalic lobe, including both 
the brain and the integuments of the species under consideration. 
The observations that we have been able to make by this method 
have not only allowed us to demonstrate the correctness of the 
opinion of Ehlers and Spengel, but have also revealed some new 
facts. 
The brain of Hunice Harassii, upon the external form of which 
we shall say nothing, seeing that this apparatus is very imper- 
fectly limited, consists essentially of a central mass of punctate 
substance, surmounted by a thick layer of nervous cells, designated 
by Ehlers the nuclear layer. 
Above this nuclear zone, and immediately beneath the cuticle, 
we see epithelial elements in the form of cones, with their apices 
directed towards the deeper surface of the integuments. The feet 
of these hypodermic cells, instead of terminating upon a basal, as in 
the case of the integuments of the rest of the body, become trans- 
formed and prolonged into so many rigid threads, which penetrate 
into the nuclear layer, grouping themselves together in larger or 
smaller numbers, to form a sort of pillar passing from the cuticle 
to the mass of punctate substance. The protoplasm of these hypo- 
dermic cells is much reduced in quantity ; their nuclei have a cha- 
racteristic fusiform aspect. The basal prolongations appear as rigid 
threads with a vitreous aspect and with a clean fracture. United 
into bundles, these hypodermic fibres are not stained readily by 
carmine or by hematoxyline; but under the influence of hemat- 
oxylic eosine they acquire the pearl-grey coloration characteristic 
of the cuticle and basals of the hypodermis of Annelides. It is 
impossible to trace one of these filaments from the hypodermic cell 
to which it belongs to the punctate substance ; they lose themselves 
in the nuclear layer, where they become intimately confounded with 
other fibrille presenting similar histological characters, but haying ~ 
a different origin. 
The nuclear layer is justly regarded by Ehlers and Spengel as of 
neryous nature, but it is composed of elements of varied aspect. 
In a section this layer appears as a delicate network filling up the 
space between the pillars of which we have just spoken, and the 
meshes of which are occupied each by a spherical nucleus. It is 
