734 DISTRIBUTION AND MEDICINAL SIGNIFICANCE. 



even greater than the breadth, so that this feature, formerly so charac- 

 teristic of Bothriocephalus, disappears more or less completely. And 

 this is all the more apt to take place from the fact that in such cases 

 the uterus is usually considerably distended, and exhibits loops far 

 separated from one another ; so that, in place of the usual rosette-like 

 form, a structure arises which is at first sight almost Tsenioid in 

 character. But in spite of their different appearance, these worms do 

 not really differ from the typical Bothriocephalus. One has only, as 

 Botticher has shown, to treat them with warm water in order to see 

 the joints greatly shorten, with simultaneous increase in breadth, until 

 they finally assume the usual form of Bothriocephalus latus. 



Not only the joints, however, but also the neck and head, assume, 

 according to circumstances, a different form. The former is at one 

 A B time slender and stretched out, so that the segmentation 



only begins at a distance of 15-25 mm. behind the 

 head, where the breadth amounts to perhaps 0'25 mm. 

 (Fig. 357), and at another time (Fig. 358) very broad and 

 thick (1*5-2 mm.), and so short that the segmentation 

 can be traced almost up to the head. The appearance 

 of the latter is just as variable. During life, and even 

 under the eye of the observer, it often changes its oval 

 form (Fig. 358) for one more like a club. Further, the 

 _ anterior end appears at one time flattened out, at an- 

 Ciub-shaped head other more pointed ; the border of the suctorial grooves 



j s sometimes straight and sometimes undulating, while 



latus. A, Seen D . ' 



from the edge ; the grooves themselves may be either narrow and con- 

 B, From the flat tracted or wide open. All these states may be occa- 



surface. (x8.) . ,, , . . 



sionally observed in preserved specimens. 



In our description we have already shown to what considerable 

 size Bothriocephalus may grow. Nor is even the length there men- 

 tioned the maximum which the worm may attain. Pallas mentions 

 a specimen 56 feet long, and from other quarters also we have heard 

 of unusually long specimens. If we consider that the worm does not, 

 like the large-jointed Tcenice, throw off the proglottides singly, but in 

 portions several feet in length, and at irregular and often long inter- 

 vals, and if, on the basis of the vegetative conditions established by 

 Braun (8*8 cm. per day), we estimate the yearly growth approximately 

 at 100 feet, it will be seen that the existence of such gigantic worms 

 is by no means an impossibility. 



This estimate of the growth almost entirely agrees with the state- 

 ment of Eschricht regarding a patient suffering from Bothriocephalus, 

 who within a year voided 70 feet of tape- worm, 20 of which, it is true, 

 belonged to the parasite itself, which finally found an exit along with 



