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REPORT ON ZOOLOGY, MDCCCXLII : 
I was never able to trace a connection between this opening and either of 
the tubes which run along the abdomen ; nay, it has sometimes appeared, 
that this mouth was nothing but a superficial deepening of the tender 
cuticle which arches the anterior end of the body. Dujardin has cor- 
rectly recognised the threads of the fibrous layer situated under the 
epidermis, which cross each other in an oblique direction. He has not 
been able to find the small tubes on the two brown longitudinal stripes, 
held by Charvet and Berthold for abdominal and dorsal vessels. The 
muscular layer lying under the cuticular covering, he agrees with the 
reporter, in describing as composed of longitudinal fibres, which lie on 
each other in lamellae. He found the cavity of the muscular cylinder 
filled with a cellular mass, enclosing a longitudinal canal, containing a 
homogeneous white mass. Under the name of Gordius tolosanus, Du- 
jardin describes a new species (ibid. p. 146) ; but the reporter cannot 
perceive that it differs from Gordius aquaticus. He observed the epi- 
dermis of the female individuals with rounded caudal end, to be com- 
posed of many-cornered convex cells, while that of the males, with 
forked caudal end, had quite a different construction, as here and there, 
between the cells of the epithelium, larger projecting spots (disques) lay 
scattered. The fibrous layer following on the epidermis, the muscular 
layer, and the cellular tissue filling the cavity of the body, he describes 
in the Gordius tolosanus, $ and $, quite as they are in Gordius aqua- 
ticus. He recognised, in the individual cells of the cellular tissue, dis- 
tinctly, the nucleus and the fine granular contents ; he also found here, 
that the cellular tissue enclosed a double canal, which was filled with a 
homogeneous substance. It is a pity that Dujardin did not examine this 
exactly with the microscope, as his practised eye might have succeeded 
in finding out the difference between the contents of the testicular and 
ovarian tubes. 
In this Gordius also, Dujardin found the head end imperforate, and 
covered with a transparent cape ; behind the head he perceived a small 
opening. He gives the colour of this Gordius as blackish ; the males, 
which were darker than the females, had an oblong aperture before the 
caudal fork, while the females were perforated obliquely at the rounded 
caudal end. 
The specific difference between G. aquaticus and G. tolosanus, as 
given by Dujardin, is, that the latter possesses an epidermis minutely 
reticulated, and the former has no epidermis. This distinction certainly 
arises only from an error in Dujardin’s observations. 
Dujardin has described another animal allied to the Gordius, under 
the name of Mermis nigrescens (ibid. p. 129, and ITnstitut. 1842, 
p. 256 ; also Archiv. Gen. de Medecine, t. xiv. 1842, p. 488). This 
worm was found very abundantly after rain, on moist ground, and some- 
times also after a strong morning dew, on newly delved beds. He 
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