842 



DR. F. E. BEDDARD ON A 



was posteriorly of a I'atlier delicate appearance, rather translucent, 

 and the proglottids were very short and enormously wide in 

 proportion. There was no increase in length of the proglottids 

 towards the end of the body, and their proportions were as in the 

 asexual worm. It would hardly, of course, be sufficient to insist 

 upon an identity upon these grounds alone ; but, taken in con- 

 junction with other facts which will be dealt with, the similarity 

 in outward appearance is very striking. The " tail " end of the 

 body ajDpeared to be a little excavated, as is common in tapeworms, 

 the penultimate segments slightly embracing the last segment, 

 which was not quite so wide. I can believe that the worm was 

 proliferating at this end. 



The scolex was not quite so wide as the ensuing strobila, and no 

 appreciable neck separated the two. The scolex is proportionately 

 large, as is indicated in the accompanying text-figure (text-fig. 

 118), and well armed anteriorly with two rows of hooks altei-- 

 nating in position. The anterior circle of hooks consisted of 16 

 separate hooks, which were about twice the size of those of the 

 succeeding circle, whose number I did not count, but which were 

 presumably the same, as they were implanted between the larger 

 hooks. The usual four suckers are present ; they show no un- 

 usual features and are unarmed ; their cavity looks forwards. 



I have investigated the internal structure by means of trans- 

 verse and sagittal sections. The cortical layer does not differ 

 greatly from the medullary layer in thickness, and the general 

 appearance of the sections is very like that of sections of the 

 immature worm (see text-fig. 119). The cortex, for example, is 

 identical or nearly so. The same bundles of longitudinal fibres 

 occur and are veiy much of the same thickness. They are also 

 separated from the medulla by transversely running fibres. I 

 have described and figui'ed in the asexual form the bundle or 

 bundles of rather stouter longitudinal fibres running outside of 

 the nei've-cord on either side and associated with a cavity dubiously 

 related to the excretory system. I find the same arrangement in 

 the sexual worm. 



The excretory system does not need a very long description, 

 since it agrees in its main peculiarities with that of the supposed 

 asexual form. There are, in fact, the same two lateral vessels on 

 either side lying parallel to each other. They are, moreover, 

 roughly equisizecl, and the innermost of the two has very thick 

 muscular walls, the fibres being circular in their disposition. I 

 should add that nuclei interspersed among these fibres were very 

 obvious. In addition to these two longitudinal trunks each pro- 

 glottid possesses a transverse vessel which has the same remarkable 

 mode of union with the ventral excretory tube that I have figured 

 (see text-fig. 115) and described (see p. 830) in the presumed 

 Cysticercoid stage, and which I need not redescribe here as the 

 structure seems to be identical. There is, however, one important 

 difference which the sexual form shows from the Cysticercoid ; and 

 that is the absence in the former of the peripheral water vascular 



