184 NEW BOOKS, WITH SHORT NOTICES. [Sna^M^^^ 
acid, osmic acid, oxalic acid, chloride of gold, oxalate of ammonia, 
nitrate of silver, Lockliart Clarke's acetic acid and alcohol, Mueller's 
liquid, chromic acid, and alcohol. In the next place the author 
commences his description of the Pacinian corpuscle, giving a 
distinct section to each of its constituents. His descriptions of 
the minute anatomy extend over more than forty pages 4to, and 
are accompanied by five plates, with nearly forty beautifully- 
drawn figures of the different parts of the corpuscles, as seen with 
powers varying from 300 to 600 diameters. The following are 
the more important results which the author arrives at : — 
1. Every Pacinian corpuscle, whether of the mammifera or 
birds, is in reality formed of three parts, — an external envelope, 
more or less compound and intricate ; an internal nucleus or club ; 
and a nervouB f bre. 
2. The envelope of the Pacinian corpuscles in the mammifera 
differs, by certain peculiarities, from those of birds. In the 
former it consists entirely of many membranous layers, or cap- 
sules, enclosed the one within the other, of which the outer 
layers have larger spaces between them than the internal ; in the 
latter, besides that the caj)sules are much less in number and very 
slightly separated, they have in addition a peculiar connective 
substance, which occupies the space between the capsule and the 
internal nucleus or club. 
3. Generally from one capsule to the other spring fine inter- 
mediate membranes, which divide each of the larger spaces into 
many small ones, which are normally filled with a clear 
albuminous fluid. 
4. The nuclei of the capsule, as they are generally called, 
are nothing but true connective-tissue corpuscles. 
5. In the Pacinian corpuscles of mammifera, the above-men- 
tioned intercapsular ligament is of two kinds ; one is but a very 
minute canal, through which runs one or two extremely fine blood- 
vessels ; the other is composed of a certain number of connections 
between caj^sule and capsule, together with ramifying connective- 
tissue corpuscles. Of the two forms of ligament, the first is fre- 
quently to be met with in the Pacinian corpuscles of man ; the 
second in those of the cat. In the corpuscles of birds there has never 
been found any but the second form of intercapsular ligament. 
6. The internal club-shaped body consists of two distinct 
parts, — a very fine envelope, and a homogeneous connective sub- 
stance. From the inside of the envelope spring several minute 
membranous filaments, which insinuate themselves into its sub- 
stance, and divide it with great regularity into numerous small 
portions, and thus help to give it sufiicient solidity and support. 
7. The nuclei from which the internal " club " is nourished, 
are situated between the membranous envelope and the connective 
homogeneous substance. 
8. In the Pacinian corpuscles of birds, the internal club-shaped 
body is probably of a less complicated texture than that of the 
Pacinian corpuscles of mammifera, from which it is chiefly 
