DK. T. S. COBBOLD ON SIMONDSIA PARADOX A. 361 



female, however, at a line corresponding with the spines, gives a breadth of fully -£% of 

 an inch. The intestinal tract is simple in both sexes, and terminates close to the end of 

 the tail ; but in the female the gut is much widened within the caudal enlargement of 

 the body. In either sex, the oesophagus is of great length, measuring fully ^ of an inch 

 from the mouth to commencement of the chylous intestine. The lateral oral papillae 

 give a length of about 3-^ of an inch from base to apex. As regards the reproductive 

 organs of the male worm, we find two long, elastic, and very delicate spicules, each 

 measuring about the -£g of an inch in length, and only little more than the xcfoo of 

 an inch in breadth. In the male, both the intestine and the sexual organs terminate 

 in the usual manner. In the female the whole mass of the ovarian filaments, together 

 with the tuba? and uterine branches, are lodged within the rosette ; but where the vulva is 

 situated could not be ascertained with certainty. The junction between the tuba? and 

 horns of the uterus is particularly well marked (PL XXXVII. fig. 2, a) ; but the mode 

 of union of the uterine horns with the rosette was not observed. Although no vulva was 

 actually seen, it may be surmised to terminate somewhere at the base of the rosette in the 

 ventral line. 



The eggs of Simondsia are small in size and extremely numerous (PI. XXXVII. fig. 5). 

 Always more or less elongated, their figure varies considerably, some being oval, others 

 elliptical, with a tendency to become constricted at one or both sides. Some of them 

 finally assume either a reniform or even a more or less hourglass-shaped figure 

 (PL XXXVII. fig. 6). Their average length is from g^y to ^}q of an inch, their breadth 

 at the centre in constricted specimens being sometimes less than the ^"oVo °f an inch. 

 Their walls display a double contour ; and the more advanced of them contain imperfectly 

 developed embryos. 



DESCPJPTION OF PLATE XXXVII. 



Fig. 1. Female Simondsia paradoxa removed from its cyst : a, head; b, b, lateral aire; c, lower end of 

 oesophagus; d d, chylous intestine ; e, e, e, cseca of the rosette; /, tail, x 12 diameters. 



Fig. 2. Detached rosette, with horns of the uterus partly drawn out from the interior : a, a, junction of 

 the tubse with the upper ends of the horns ; b, b, b, uterine branches, x 12 diam. 



Fig. 3. Small male Simondsia paradoxa : a, head ; b, tail. xl:' diam. 



Fig. 4. Section of the wall of the stomach of Sus scrofa, showing the interior of a parasite-bearing cyst 

 exposed by transverse section : a, lower half of the cyst ; b, b, b, secondary and ultimate depres- 

 sions, x 6 diam. 



Fig. 5. Fragment of one of the uterine horns, showing numerous ova in the interior. x 150 diam. 



Fig. 6. Group of eggs, removed from the above, x 250 diam. 



Fig. 7. Outline of the tail of the male worm : a, anus ; b, spicules, x 32 diam. Outlined with the aid 

 of a camera. Original. 



SECOND SERIES. — ZOOLOGY/, VOE. II. 52 



