THE FISSHJEMMATION OF T.ENIA. 



83 



fissigemmate progeny of Myrianida approach nearest to the idea 

 of a fully developed, complete individual, the joints of Tasnia 

 stand the farthest off. 



That you may the more 

 fully understand this, let me 

 state that Taenia has no 

 intestine whatever, and that 

 it possesses the merest trace 

 of a nervous system, only 

 a simple knot or ganglion 

 which gives off a slender 

 branch to each one of the four 

 suckers that project from the 

 four corners of the head (H). 

 The only organ which seems 

 to be common to the whole 

 body is a sort of circulatory 

 system, consisting of four 

 slender channels, which, be- 

 ginning at the head, extend, 

 one on each side above and 

 below, along the entire length 

 of the animal, and commu- 

 nicate with each other from 

 point to point by a trans- 

 verse canal, which runs across the forward end of each joint. 

 In some kinds of tape-worms these channels are distrib- 

 uted in the form of an irregular net -work, which here and 

 there has minute openings at the surface of the body, by 

 which they communicate with the surrounding fluids of the an- 



Fig. 44. "Tcenia solium. Linne. Natural size. Only such parts are rep- 

 resented as are characteristic for the shape of the joints. H, the head; a, 309th 

 joint; 6, 448th joint; c, 569th joint; </, 680th joint; e, 768th joint; / 849th 

 joint; g, 855th joint, and last but one. This worm measured 3299 raillim. 

 (10 feet 9 inches)." o, o 1 , the apertures of the reproductive organs. From 

 Wcinland. 



Fig. 44. 



