TAENIA ECHINOCOCCUS. 269 



Having no space to dwell further on this question, it re- 

 mains for me to observe that a distinct water- vascular system is 

 recognizable in these scolices, being also connected by the interven- 

 tion of the stalk-like neck of the scolex, with the endocystic layer 

 of the brood-capsule, and also, therefore, with the vessels of the 

 maternal endocyst. In the scolex, according to Leackart, there 

 exists a circular channel immediately below the rostellum, and 

 this ring, on either side, gives off two vessels which pass down- 

 wards in a tortuous manner on either side of the scolex, internally, 

 until they arrive at the pedicle where they unite to form two chan- 

 nels, which latter are continued into the vascular system of the 

 maternal endocyst. In the retracted condition of the scolex, their 

 position, of course, becomes very much altered, and they form loops 

 on either side of the central line which marks the space leading 

 down to the now inverted head. Neither Huxley nor myself have 

 seen these vessels in the scolex itself, but Huxley discerned some 

 apparently loose cilia in the granular parenchyma of the body, the 

 longitudinal measurement of these free filaments being about the 

 3^ of ^n inch (Fig. 4, Plate XIII). Further into the morphological 

 changes exhibited by the retracted scolices I need not enter. 



But now comes the curious question respecting the singular 

 phenomenon termed proliferation. Here, also, must I be brief, 

 and, to avoid circumlocution, at once observe that the endocyst 

 is, as recently shown by Naumyn,"* primarily concerned in the pro- 

 duction of the secondary and tertiary hydatids, whether they be 

 exogenous or whether they be endogenous. In point of fact, they 

 are special bud-developments which, instead of becoming brood- 

 capsules, become daughter vesicles and grand-daughter vesicles, 

 constantly developing in their interior secondary and tertiary brood- 

 capsules and scohces, but sometimes, it would appear, developing 

 neither the one nor the other. Without attempting a detailed 

 exposition of all these singular and interesting phenomena, I shall 

 adduce a lengthened passage from Leuckart, which will probably 



* " Dissert. luaug. Berol." 1862, in " Arciiiv. fiir Anat. unci Physiol.," 1862, s. 612. 



