282 
Taenia crassicollis 
Both vagina and vas deferens pass ventral of the longitudinal ex¬ 
cretory canals and nerves on their way to the exterior. The genital pore 
is usually single in each segment, situated on any one wing of the worm, 
but there are, sometimes, two genital pores lying respectively on any 
two wings of a segment. 
There is no need to mention in detail the other internal structures 
such as the musculature, nervous system, abundant presence of the 
calcareous corpu.scles, etc., because they agree in all respects with those 
of normal T, crassicollis. 
EXPLANATION OF PLATE XX. 
Lettering:—C, cirrus; cp, cirrus pouch; D, yolk-gland; DV, dorsal canal; H, testes; 
N, nerves; OF, ovary; Sg, shell-gland; TM, transverse muscles; TV, transverse 
canal; XJt, uterus ; Vd, vas deferens ; Vg, vagina ; FF, ventral canal. 
Fig. 1. Scolex and anterior segments. {x 1.5.) 
Fig. 2. 100th to 120th segments from the last. ( x 2.) 
Fig. 8. 50th to 57th segments from the last. ( x 2.) 
Fig. 4. 20th to 26th segments from the last. (x 2.) 
Fig. 5. Last 7 segments. (x2.) 
Fig. 6. Central portion of cross section at the level of female glands. 
Fig. 7. Cross section of posterior end of segment showing the connexion of transverse 
and ventral canals of excretory system. 
Fig. 8. Cross section of mature segment showing testes and branched uterus. 
Fig. 9. Cross section of segment at the level of cirrus pouch. 
