A revision of the adult tapeworms of hares and rabbits / by Ch. Wardell Stiles.
- Charles Wardell Stiles
- Date:
- [1896]
Licence: Public Domain Mark
Credit: A revision of the adult tapeworms of hares and rabbits / by Ch. Wardell Stiles. Source: Wellcome Collection.
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![DAVAINEA SALMONI, Stiles, i8gs. (Plate XXII, figs. 3-4; Plate XXIII, figs. 1-9; Plate XXIV, figs. 1-2; Plate XXV, figs. 1-11..) 1887, u Tcenia jjectinata,” Goeze, 1782, of Curtice ex parte, Science [N. Y.], March 23. 1895, Davainea salmoni, Stiles, Veterinary Magazine, II, June, p. 343. Aug. 28,1895. The length of type specimen, mounted (Bureau of Animal Industry Cestode series No. 1196), is 86 mm.; the broadest segments attain 3 mm. in width. Total number of segments about 450 (the exact number could not be ascertained because of contraction at certain points), of which about 230 belong to the first third of the worm. Head 0.‘736 mm. broad by 0.496 long. Retracted rostellum 0.144 mm. in diameter, provided with a double crown of minute hooks, of characteristic Davainea form, 20 )a long, about 60 hooks in each row. The suckers are large and prominent and armed with rows of closely set hooks, the number of which it is utterly impossible to count; they may be estimated at about 750; the size of these hooks varies, the prong of the longest reaching 10 jj.. The neck is thin (0.480 min. broad) and short, segmentation beginning about 0.8 mm. back of the head. The segments vary extremely according to contraction, most of them being broad and short, but others being infundibuliform and nearly as long as broad. Within the proximal third of the strobila variations may be found between seg- ments 0.512 mm. broad by 32 yu long and 0.7 mm. broad by 0.528 mm. long. The anlage of the genital organs first appears in about the one hundred and seventieth segment, as a darkly staining body, one end of which is in the median line, the other pointed toward the pore side of the segment. As the segments are followed distally this body assumes the characteristic pistol shape found in the genital anlagen of so many tapeworms (Moniezia, etc.); the muzzle of the barrel rapidly reaching the lateral margin at the genital pore; the barrel divides into two parallel canals, the vas deferens proximally, the vagina distally, while the handle of the pistol grows distally in the median line to form the female glands in approximately the middle of the segment. The genital pores are irregularly alternate, and vary in position from the middle to near the anterior edge of the margin. The testicles appear at about the two hundred and thirtieth segment, and occupy almost the entire median field. The condition of the material does not warrant a description of the changes the female anlage undergoes, further than to state that the glandular portion divides into two (or probably three) bodies. The anterior body will by analogy represent the ovary, the distal body the vitellogene gland; the third (very indistinct) body would probably represent the shell gland. Canals could be seen between these glands, but could not be analyzed. The development of the uterus could not be followed, but after about the three hundred and fortieth segment groups of eggs gradually appear, suppressing](https://iiif.wellcomecollection.org/image/b28058124_0056.jp2/full/800%2C/0/default.jpg)
