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REPORT ON ZOOLOGY, MDCCCXLIl : 
through which the Thallack flows, and surrounded by two rows of lofty 
calcareous hills, that furnish a very hard water, containing many earthy 
ingredients. The soil is very damp ; and most of the buildings stand 
upon wet foundations, so that cellars are rarely to be met with. The 
food of the inhabitants is mostly meal, salted and smoked beef, and 
much pork. The disease of worms is here very common, and has been 
so from a very remote period. Tcenia solium and Ascaris lumhricoides 
are particularly abundant. Now, a league beyond this district, the 
disease is very rare. 
GOEDIACEA. 
An Essay by Berthold, published some years since, has again appeared 
last year, with additions, “ tlber den Bau des Wasserkalbes {Gordius 
aquaticus), Gotting. 1842,” and deserves our attention so much the 
more, as, till very lately, our knowledge of this animal has been very 
defective. When the reporter places the Gordiacea as a separate 
order of Helminthes, he has convinced himself, in the most precise 
manner, by direct observation, of the entozootic life, which, at certain 
times, the Gordius aquaticus leads ; but he could not resolve to incor- 
porate it with the Nematoidea, since it diflbrs remarkably in its ana- 
tomical structure. 
Berthold found the Gordius aquaticus generally in brooks and small 
springs about Gottingen. Its colour is sometimes a bright, sometimes a 
more sombre brown. The head-end forms a white, semi-transparent 
arch behind, which the dark hue makes a sort of ring, from which two 
dusky-coloured stripes rmi longitudinally down the whole body ; the pos- 
terior end of the body presents a horizontally lying fork, at the under 
angle of which the anus opens. The reporter must here correct Ber- 
thold’s assertion, that this fork is only present in male individuals ; for, 
according to his experience, there are not so many male Gordii to be 
met with as females, which possess a rounded anal extremity. The anal 
opening (which the reporter besides considers as the sexual opening) is 
found in the female, in the centre of the obtuse end of the tail. Ber- 
thold describes the cuticle of the Gordius as composed of two layers, the 
outer consisting of a reticulated tissue, the meshes being bounded by six 
unequal sides, and pores are present where the mesh-threads meet at 
the different angles. This membrane, according to Berthold, is very 
vascular ; but the reporter could neither discover the vessels, nor the 
pores mentioned by him. He recognised in it only an epidermis, 
composed of an angularly-netted epithelium, the cells of which were 
arched somewhat outwardly; and probably Berthold took the calibre 
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