QUARTERLY CHRONICLE. 147 
remarked that there was congestion of the blood-vessels of 
the nerve-roots of the spinal cord, accompanied by an in- 
crease in volume of the interstitial reservours or cavities. 
5th. From all that the author adduces we may conclude 
that a single drop of an energetic poison like nicotine is 
sufficient to killa big animal, not because it chemically upsets 
the various metamorphoses of the system, but because the 
poison destroys the little organs like nerve-cells which are 
the origin of the principal vital nerves. 
6th. The effect of opium and chloroform on the myeline 
is to give it the appearance of a number of little brilliant 
bodies united, instead of being amorphous. 
Structure of the Frog’s Cornea—Dr. Von Recklinghausen 
describes certain movable corpuscles visible in the cornea of 
the frog, when properly treated. He argues the existence of 
channels and lacune in the cornea, from the movement of 
these corpuscles. The invisibility of the channels or lacunz 
themselves is, according to this gentleman’s view, owing to 
the fact that they contain a fluid of the same refracting power 
us the corneal tissue. (‘Schmidt’s Jahrbiicher,’ 1864, 11.) 
The Retina of the Whale.—This has been made the subject 
of investigation by Herr Ritter, who describes the structure 
of the granular layer in that animal :—The layer consists of 
three kinds of fibres. 1st. The fibres of the limiting mem- 
brane. 2nd. The branching of the nerve-cells. 3rd. The 
processes of the rods and cones. The fibres of the limitans 
interweave and form a beautiful meshwork, coarser near the 
“ora serrata.” The processes of the rods branch throughout 
this network, and finally form the branches of the cells pro- 
perly so called. In the centre of the retina the processcs 
of the rods run straight, and rarely combine; as they ap- 
proach the ‘ora serrata’ they combine more frequently, and 
become broader. Hence the granular layer in the centre is 
narrower, and consist of finer fibres. Herr Ritter proposes 
the name outer fibrous layer, instead of granular layer, which 
he considers objectionable. (‘ Henle und Pfeufer’s Zeitschrift,’ 
vol. xxi, part 3.) 
Structure of the Kidney.—According to the observations of 
Mr. B. Wells Richardson, the Malpighian tufts of the kidney 
have not one, but two efferent vessels; thus, this gentleman 
confirms the observations of Beale and Virchow. A writer in 
one of our contemporaries suggests that the quasi-second tube 
may belong to a subjacent uninjected tuft, and, owing to the 
thickness of the section, appears to originate in the upper and 
more visible tuft. (‘ Dublin Med. Press,’ vol. ix, p. 489; and 
‘Pop. Se. Rev.,’ Jan., 1865.) 
VOL. V.—NEW SER. L 
