520 



ORGANIZATION OF T^EXIA SOLIUM. 



Fio. 289. 



FIG. 290. 



an almost comb-like structure. The same is often noticed in the 

 distal off-shoots of the last lateral branches, but in their case this 

 structure is less striking, partly because their 

 number is more limited, and partly also be- 

 cause the associated lateral branches turn 

 aside very regularly from their transverse 

 position, and run in a curved direction towards 

 the posterior angles. Otherwise they are 

 scarcely to be distinguished from the others. 

 The space marked off by them has the form of 

 a flat, obtuse-angled triangle, and very gener- 

 ally contains at its angles the remains of the 

 shell-gland. After what has already been 

 said regarding the connection of the uterine 

 structure with the state of general organiza- 

 tion, it hardly needs to be expressly mentioned 

 that in the proglottides of T. solium the 

 ramifications of the uterus are much farther 

 from the edge posteriorly than anteriorly. The 

 transverse anastomoses of the lateral vessels 

 FIG. 289. Two segments of ii m it the further distribution of the uterine 



Tcenia solium with branched 



uterus. ( x 3.) 



FIG. 290. Pmgiottis of 



, i 



branches. 



Although the uterine branches are, as a rule, 

 solium with slightly w j(j er tnan j n Tccnia saginata, and are also not 



branched uterus, (x 2.) 



unfrequently swollen into a club-like shape, 



the number of eggs contained by the joints is smaller. Thus it 

 appears that both in respect of the fertility of the individual segments 

 as well as of the general character of the chain, T. solium is far behind 

 T. saginata in its economic relations. This disparity is sometimes 

 very marked in individual specimens ; for (as is shown in the above 

 picture of a very unfruitful joint, Fig. 290) there are some tape-worms 

 whose lateral branches neither attain their normal length nor ramify 

 as usual, but remain more or less abortive. 



Although Weinland asserts that he once found proglottides like 

 those depicted above in a bookless Tccnia, we may safely assume, on 

 the ground of later investigations, that they never originate from T. 

 saginata. Whenever the associated worm has been investigated, its 

 head and the formation of its joints have always proved it to be 

 Tcenia solium. 



The head of the species, as has been repeatedly noted, differs from 

 that of T. saginata chiefly in the possession of a hook-apparatus ; but 

 this difference, although the most important and the most striking, is 

 by no means the only one. Other peculiarities of the species are 



