LAWSON, ON LIMAX MAXIMUS. BF 
number of delicate threads, which become lost between the 
endoplasts of the ganglion itself. On no occasion have I been 
enabled to discover the division of the ganglion into compart- 
ments, as described by Von Siebold. I have carefully pre- 
pared sections with the assistance of Valentin’s knife, and 
have subjected these slices to the action of the compressorium, 
and in both cases the same appearance was presented to the 
eye, Viz., an opaque periplast, consisting of fatty matter and 
calcareous particles (as evidenced by transparence ensuing on 
immersion in a mixture of acetic acid and ether), imbedding 
numerous large, and readily perceivable endoplasts of the fol- 
lowing kinds : 
A. With an outer wall, granular contents, and a well- 
defined nucleus and nucleolus. 
B. With two outer walls, the substance between the two 
clear and non-granular; the interior filled with a granular 
material, a nucleus, and two or three well-marked nucleoli 
fig. 7). 
; Both varieties were of an irregularly elliptical outline, 
large and small, but never pedunculated. From Ehren- 
berg’s observations on Arion, I had expected to find tailed 
globules in Limax, but they have no existence. Anderson’s* 
woodcut is calculated to mislead, because he has not given 
the proper number of nerves arising from either the superior, 
or inferior ganglia, and, besides, he has fallen into error in 
representing two pairs of filaments as united to the bands 
connecting the supra- and infra-cesophageal centres ; and one 
would suppose from his engraving, that the pharyngeal 
nervous masses had no direct connection with the others. It 
might be objected to the foregoing account, that, I have taken 
no cognizance of the splanchnic series as a special system ; 
but I would reply, that on this subject I hold the opinions or 
M. Claude Bernard} to be in the main correct. 
Sense System.—Organs of Hearing.—lt is stated in most 
works on the anatomy of molluscs that these organs are 
represented bya pair of transparent, membranous saccules, 
containing either siliceous or calcareous particles termed 
otolites, and placed upon the inferior nervous masses. I 
frankly confess that I have never succeeded in finding them 
present in Limax. I have taken great pains to detect them, 
but im vain, and although naturally anxious to discover some 
* © Cyclopedia of Anatomy and Physiology ;? Article ‘“‘ Nervous System ;” 
Division ‘‘ Comparative Anatomy.” 
+ ‘Med. Times and Gazette,’ vol. for 1861; and ‘ Journ. de Physiologie.’ 
