13 



long been a subject of dispute, whether the proglot- 

 tides should be considered as independent zoonites, 

 derived from the Tsenia, this latter therefore being 

 regarded as a compound creation, formed of 'a colony 

 of simple ones ; or whether they should be considered 

 as parts of a single individual. Weinland is of the 

 opinion that the first is the true view ; i.e., tiiat the 

 whole tapeworm should be considered, not as one 

 individual, but as a group of individuals, to be com- 

 pared to the many individual Medusae which are 

 formed out of the Hydra fusca by transverse division. 

 Von Siebold also entertains the same view of them, 

 and considers their ability of locomotion, already 

 spoken of, as a point in favor of it. These articula- 

 tions are important parts of the parasite, containing, 

 as they do, their sexual organization. Each one is 

 androgynous ; i.e., containing in themselves the male 

 and female genitalia united. The genital pore (PI. I. 

 fig. 4, A) is situated upon the margin of the joint, 

 sometimes upon alternate sides, but often occurring 

 for three or four times upon one side, and then upon 

 the other (Moquin-Tandon). These first appear at the 

 317th joint, in the form of prominences ; at the 350th, 

 the pores themselves are distinct (Kiichenmeister). 

 This genital pore is very apparent, and opens at the 

 summit of a mamillated projection (Moquin-Tan- 

 don). This pore, examined by the microscope, ap- 

 pears like a cup-shaped depression, with two small 

 openings in it, through the anterior one of which the 

 lemniscus or rudimental penis projects (PL I. fig. 3, a). 

 This organ, which is about 0-276 mil. in length, 



