HELMINTHOLOGY-HELMINTHES CESTODES.

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Fowl, the Pike, and Roach ; the Reporter, however, is unableto extract any proper generic character, from Dujardin’sdescription, by which Proglottis can be said to be distin-guished from Tania, In the ova, provided with threesimple oval egg-cases, of Proglottis pistellum, from Sorexaraneus, Dujardin found the well-known embryos, charac-terized by six hooklets. The head of this Tapeworm possesses a proboscis with hooks. The first seven to four-teen joints are asexual, and constitute the neck of the animal,the five or six succeeding ones contain only the male organs,for at the anterior end of each of these joints there isplaced an oblong transversely-lying testis, and a lemniscusopening laterally. The next one or two joints appear to behermaphrodite, and the five last exclusively female. Thisview of the genital apparatus of the individual joints of theProglottis may easily give rise to misconceptions. Thegradual development of the joints from the neck backwardstakes place in this instance in the same way as in the otherCestoid worms; only the development of the male organs inthe invariably hermaphrodite joints commences earlier andproceeds more rapidly anteriorly than that of the female;in the most posterior, so-termed, female joints, the oviductsare so crammed with ova that the male organs, which arenever wanting in these joints but have already performedtlicir function and become collapsed, are driven altogetherinto the background by the female propagative organs.

Respecting the history of the Bothriocephalus latus,Castelli (Isis, 1843, p. 618) has communicated the noticethat he has met with this Tapeworm , which does not occurin Italy , in two Swiss soldiers serving in that country.

A Bothriocephalus from the duodenum of Salmo umbla,and which is probably new, has been discovered by H.Kolliker (Muller’s Archiv, 1843, p. 91), and employed forthe investigation of the history of the development of theCestoid worms. He found the youngest ova of this Bo-thriocephalus globular, and constituted of a vitelline mem-brane, germinal vesicle, and probably a germinal spot;