TRANSMIGRATIONS AND METAMORPHOSES. 229 



other cestodes, is free at the commencement and the end 

 of its life : at the beginning, in order to penetrate into 

 its host ; at the end, to scatter its eggs. 



Messrs. Sommer and Landois published, in 1872, an 

 anatomical description of the sexual organs of the 

 Bothriocephalus latus, of such completeness, that it 

 will be long before any one will again take up this sub- 

 ject, which had so much occupied helminthologists ever 

 since the celebrated work of Eschricht. This memoir is 

 illustrated by superb engravings, which represent these 

 organs under every aspect. Dr. Bottcher, of Dorpat, 

 found in the small intestine of a woman, who died of 

 peritonitis, at least a hundred Bothriocephali. They 

 were but slightly developed, though there were some in a 

 sexual state. 



The largest taenia, though not the longest, is the 

 Tsenia magna, from the Rhinoceros, described by Marie ; 

 it is, no doubt, the same to which the name of gigantea 

 was given by Peters. The learned director of the 

 Museum of Berlin gave me a tine specimen of it eighteen 

 years ago. The generic name of Plagiotsenia has been 

 proposed for this worm. 



Almost all birds nourish large and beautiful tsenise, 

 but they must be studied immediately after the death 

 of their host. They often change their form entirely 

 at the end of a few hours. 



Woodcocks and snipes always have their intestines 

 stuffed full of taeniae and the eggs of these worms. Every 

 bird contains them by thousands. Fortunately we can- 

 not be infested with the taenia of the snipe and the 

 woodcock. 



Fig. 61 represents the scolex of the Tsenia variabilis 



