56 ILLINOIS BIOLOGICAL MONOGRAPHS [406 



After Anoplocephala had split off the common line became modified 

 as follows: 



1. The uterus ceased to cross the excretory ducts, in anlage. 



2. The ovary moved forward and laterad so as to lie directly in 

 front of the vitelline gland with the proximal end of the oviduct in 

 front of the median line of this gland. 



3. The testes become confined to the median field. 



From this line developed Cittotaenia, Schizotaenia, and Moniezia. 

 Cittotaenia resembles Anoplocephala in some respects but the following 

 evidences of relationship to Moniezia outweigh them: 



1. In both, the uterus crosses the excretory ducts dorsally only, 

 never ventrally as in Anoplocephala, Andrya, and Aporina. In some 

 cases in each of these two genera, the uterus is confined to the median 

 field at all stages. 



2. At least one Cittotaenia has a reticulate uterus. 



3. Both have two sets of genital organs. 



4. The dorsal excretory duct is dorsal or median to the ventral 

 in most species of each. 



The points arguing for close relationship between Moniezia and 

 Schizotaenia are as follows: 



1. Each retains at least remnants of the reticulate uterus. 



2. Some individuals of Schizotaenia show asymmetry in regard to 

 the relations of the genital glands. 



3. Moniezia has, to a considerable extent, at least, the mulberry- 

 like vitelline gland, such as is found in most species of Schizotaenia. 



4. The ripe uterus is divided into compartments in some species 

 of both genera. 



Although retaining the reticulate uterus Moniezia and Schizotaenia 

 are in many ways the most specialized representatives of their subfam- 

 ily, except of course for Triplotaenia. They have specialized along 

 different lines and the decision as to which is nearest the ancestral line 

 depends upon the criteria adopted. 



The position of Bertiella in this scheme is somewhat doubtful. I 

 had no specimens at hand for study and so must depend upon the 

 accounts of others. The following points argue for close relationship 

 with the higher representatives of the genus Andrya rather than with 

 other genera. 



1. The vagina and vaginal pore are directly posterior, or poste- 

 rior and dorsal to the cirrus pouch. 



2. The cirrus pouch is either identical with the higher Andryae 



