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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 55, 



I 



view of its posterior portion appears to be embedded in or overlaid 

 by the portion of the vitellarium. which projects into the interovarian 

 field. The vagina extends in from the genital pore almost straight 

 or somewhat inclined anteriorly and curves around the nearest ovary, 

 forming the receptaculum seminis in the interovarian field. In 

 gravid segments (fig. 32) the uterine stem is very long and bears on 

 each side 8 to 14 lateral branches, which in turn send out secondary 

 branches, these branches usually distinct or with only a slight ten- 

 dency toward terminal fusion. 

 I The eggs are elliptical, 37 by 32 \i. 



Jr 1j in diameter. 



^^ ' } Hosts. — Primary : Canis fa- 



77iiUaris, C. latrans^ C. nehracen- 

 sis, Felis catus (F. domestica), 

 F. tigris, Urocyon cinereo- 

 argentatus., fox. Secondary: 

 Oryctolagus cwniculus {Lepus 

 cuniculus ferus., L. c. domesti- 

 cus), L. europaeus {L. timidus)^ 

 L. timidns {L. variabilis), Syl- 

 vilagus hrasiliensis {L. hrazil- 

 iensis), S. fyoridanus mallurue 

 (L. sylvaticus), L. calif omicus 

 w allawalla., S. floridanuf 

 ineanisii {L. mearnsi), S. palus- 

 tns {L. palustri-s) f L. ameri- 

 canus, S. auduboni haileyi, S. 

 7iuttaUi pi7ietis, Mus irtusculus, 

 mountain beaver. 



Location. — In intestine of Dri 

 marj^ host. In liver, mesenteries, 

 and free or attached in abdomi- 

 nal cavity of secondary host. 



Locality. — More or less cosmo- 

 politan. 



Life history. — Eggs produced 

 by the strobilate tapeworm pass 

 out and are ingested in contaminated food or water by the primary 

 host. The embryo is released in the digestive tract and bores its way 

 into the liver, where it begins development as a bladderworm, com- 

 monly called Cysticerous pisiformis. Usually it develops to a cer- 

 tain point and then slips out of the liver and falls into the abdom- 

 inal cavity, where it remains free for a time, ultimately becoming 

 attached by an adventitious cyst to the mesenteries as a rule. 



Of the above host records the following are new : Lepus calif omi- 

 cus wallaioalla, Sylvilagus fioridanus mearnsii, S. auduhom haileyi, 



I mm. 



Fig. 32.— Taenia pisifoemis. Geavid segment. 



