82 



SCIENCE PROGRESS. 



ganglion of the other side (Fig. II. a and d), thus forming a 

 complete ring round the body. The dorsal branch is 

 further connected with the ventral by a small commissure 

 situated just within the lateral excretory canals, which are 

 thus in the posterior region of the proglottis surrounded by 

 a nerve ring. Further, both the dorsal and the ventral 

 commissures bear two small ganglionic enlargements (Fig. 

 II. ^ and A) each of which gives off a small branch passing 

 forwards and apparently ending — though there is still some 



Fig. 2. — A diagram to illustrate the nervous system of Moniezia after Towers. 



a. Dorsal commissure. 



b. Neutral commissure. 



c. Anterior lateral ganglion giving off internal and external genital nerves. 



d. Genital pore. 



e. Marginal nerve. 



/. Posterior lateral ganglion. 

 g. Left dorsal ganglion. 

 h. Left neutral ganglion. 



doubt as to this — in the corresponding ganglion of the pre- 

 ceeding proglottis. 



Each lateral nerve cord in addition to the large ganglion 

 at the posterior end of the proglottis (posterior lateral 

 ganglion) also bears a small ganglion about the middle of 

 the length of the proglottis near the genital pore (Fig. II. c). 

 This anterior lateral ganglion gives off an internal genital 

 nerve which supplies the ovaries and uterus and an external 

 genital nerve which is distributed to the region of the 

 genital orifice. 



Tower's account of the nervous system in the Tape- 

 worm proglottis is by far the most complete that we have 



