TEICHINA SPIEALIS. 351 



the oesophagus), which becomes dilated after a short course and 

 forms a portion of intestine, which, increasing constantly in 

 thickness posteriorly, considerably exceeds the thicker abdomen 

 in length, and at first by various close convolutions, but after- 

 wards by constrictions and dilatations, resembles the appearance 

 of a necklace, in which the beads become larger posteriorly. 



At the spot where the thinner portion of the body of our 

 worm passes into the thicker and posterior portion, this monili- 

 form intestine ceases in both worms, and passes into a pyriform 

 or infundibuliform muscular portion, which may be called the 

 stomach. At the point of transition of the anterior part of the 

 intestine into the stomach there are a pair of small pedunculate, 

 alary appendages or glandules, which appear to be little caeca, 

 and which hang down rather flatly during the Trichinal existence, 

 whilst in Trichocephalus they rise forwards and upwards, close 

 to the mouthpiece of the funnel. In Trichina they are filled 

 with colourless contents, in Trichocephalus certainly with coloured 

 masses, which however are distinguished from the rest of the 

 intestine by a much lighter colour. These wing-like, csecnl 

 appendages, furnish one of the principal supports of the sys- 

 tematic diagnosis of the two worms. Hence the intestine im- 

 mediately behind the tube of the funnel passes over again into a 

 dilatation, and then runs backwards in a tolerably straight or 

 scarcely undulated line, towards the extremity of the abdomen, 

 in the centre of which it opens more or less directly. 



4. Lastly, the second tube which occurs in the abdomen 

 together with the intestinal canal, speaks above all in favour of 

 the identity of the two worms. Its anterior blind extremity 

 reaches, in Trichina, up to the level of the stomach, and looks 

 towards the other side, to which it actually crosses, and may 

 subsequently become the vagina by dehiscence, whilst the pos- 

 terior blind end grows out from the spot to which it reached 

 during the Trichina-Mis, forming all sorts of ovarian convolutions, 

 by which female Trichocephali are produced. But when male 

 Trichocephali are to be formed from Trichinae, the anterior ex- 

 tremity of this tube certainly runs over the intestine at the same 

 place, but not to the margin, but it passes backwards on the 

 other side of the intestine, and at the same time conceals itself 

 beneath the intestine. The posterior blind extremity of the 

 canal dehisces here into the intestine, a certain distance from the 



