118 



ENTOZOA. 



complicated structure to the vermiculi of the 

 Human Kchiwcoccus on his own authority, 

 and speaks doubtfully respecting the coronet 

 of hooklets and siictorious mouths of the ver- 

 miculi contained in the cyst of the Echinococcus 

 of the Sheep, Hog, &c. 



The Echinococcus hominis, (Jig. 57,) which 

 occurs in cysts in the 

 Fig. 57. liver, spleen, omen- 



turn, or mesentery, is 

 composed ofan exter- 

 nal yellow coriace- 

 ous, sometimes crus- 

 taceoustimic, and an 

 internal transparent, 

 firm, gelatinous 

 membrane. The form 

 of the contained ver- 



EMnococcws hominit. miculi is represented 

 in the magnified view 



subjoined, (fg. 58,) taken from the Elminto- 

 grufta humana of Uelle Chiaje. 



Fie. 58. 



Vermiculi of Echinococcm hominis, highly magnified. 



Miiller* has recently described a species of 

 Echinococcus voided with the urine by a young 

 man labouring under symptoms of renal disease. 

 The tunic of the containing cyst was a thick 

 white membrane, not naturally divided into 

 laminae; the animalcules floating in the con- 

 tained fluid presented a circle of hooklets and 

 four obtuse processes round the head ; the pos- 

 terior end of the body obtuse : some of them 

 were inclosed in small vesicles floating in the 

 large one ; others presented a filamentary pro- 

 cess at their obtuse end, probably a connecting 

 pedicle which had been broken through. 



Of the species entitled Echinococcus veteri- 

 tiHritm we have carefully examined several in- 

 dividuals soon after they were extracted from 

 the recently-killed animal, (a sow, in which 

 they existed in great abundance in cysts in the 

 abdomen.) The containing cysts were com- 

 posed of two layers, artificially separable, 

 both of a gelatinous texture, nearly colourless 

 and subtransparent, the external one being the 

 firmest. The contained fluid was colourless 

 and limpid, with a few granular bodies floating 



OtcuUt suctoria quatuor j an haec in omnibus ? Ipse 

 saltnm in suis Echinococcis non vi<li, sed (him Be- 

 rolini rcrpns examinarem, microscopic solito et 

 bonu dcKlttutus cram. Hist. Kntox. 



* Archiv fur Physiol. (Jahresbericht), 1830. 



in it, and immense numbers of extremely mi- 

 nute particles applied but not adherent to the 

 internal surface of the cyst. On examining 

 these particles with a high magnifying power, 

 they were seen to be living animalcules of an 

 ovate form, moving freely by means of superfi- 

 cial vibratile cilia, having an orifice at the smaller 

 end from which a granular and glairy substance 

 was occasionally discharged, and a trilobate de- 

 pression at the greater and anterior extremity 

 produced by the retraction of part of the body. 

 I watched attentively and for a long period a 

 number of these animalcules in the hope of 

 seeing the head completely protruded, but with- 

 out success. On compressing the animalcule 

 between plates of glass, a group of long, slen- 

 der, straight, sharp-pointed spines became vi- 

 sible within the body, at its anterior part, and 

 directed towards the anterior depression, pre- 

 cisely resembling the parts described and fi- 

 gured by Ehrenberg as the teeth of the Poly- 

 gastric Infusories ; the rest of the body was 

 occupied by large clear globules, the stomachs? 

 and smaller granules. Animalcules thus orga- 

 nized, it is evident, cannot be classed with cystic 

 Kntozoa, but must be referred to the Polygastric 

 Infusoria. 



The globular cyst which is commonly deve- 

 loped in the brain of Sheep differs from the 

 Echinococcus in having organically attached to 

 itanumber of small vermiform appendages, pro- 

 vided severally with suctorious orifices, and an 

 uncinated rostellum, similar to those in the head 

 of the Armed Tsenia;. But as this cystic genus, 

 denominated Ctrnurus, (xoio;, communis, mga, 

 cauda, from the terminal cyst being common 

 to many bodies and heads,) is not met with in 

 the human subject, a simple notice of it is here 

 sufficient. 



When the dilated cyst forms the termina- 

 tion of a single Entozoon, organized as above 

 described, it is termed Cynticercus, (xvtrrtf, 

 vesica, xtfxof, cauda), and of this genus there 

 are several species, distinguished for the 

 most part by the forms and proportions of 

 the neck or body intervening between the 

 head and the cyst ; as for example, the Cyst. 

 Jitsciolaris, Cyst. Jistuluris, Cyst, longicoltis, 

 Cyst. tenuicotlis, &c. The only species of 

 this genus known to infest the human body 

 is the Cysticercus ccllulostc, Rud. (the Hydatis 

 Finna of ISlumenbach). It is developed, 

 like the Trichina, in the interfascicular cel- 

 lular tissue of the muscles, and, like it, is in- 

 variably surrounded by an adventitious cap- 

 sule of the surrounding substance condensed 

 by the adhesive inflammation. Fig. 59 exhi- 



Fig. 59. 



I'ortion of human muscle, with Cysticemu cdliitosa:. 



