14 Earle C. Stevenson 



key to classification of T. serrata and T. scrialis 



Subfamily Tacniinae. Diagnosis. Taeniidae: Large species, 

 strobila segmented, with the ripe segments longer than broad. 

 Scolex with a short, rudimentary rostellum armed with a double 

 crown of hooks. In some instances the rostellum is modified into 

 a sucker, whose armament becomes rudimentary and disappears. 

 Genital pores irregularly alternate; usually large numbers of 

 testes in lateral portions of median field ; yolk gland, shell gland, 

 and ovary in posterior half of median zone. Uterus with a me- 

 dian stem developing lateral branches, which in the ripe segments 

 entirely obliterate the other genital organs. Egg shell thin and 

 delicate ; embryonic shell thick and richly striated. Encysted 

 stage in plant-eating mammals : adult in man and flesh-eating 

 mammals. 



Genus Taenia. Diagnosis. Taeniinae: Same characters as 

 subfamily. 



Species Taenia serrata. Diagnosis. Taenia: Strobila ser- 

 rated, 60 cm. to 2 m. in length; head from 1.5 to 2.0 mm. in 

 diameter, bearing 4 suckers, one at each corner. Short rostellum 

 armed with a double crown of 34 to 48 hooks : large hooks (inner 

 row), 246 to 294 jul in length; small hooks (outer row), 132,1*. to 

 177/x in length. Ventral root of small hooks bifid. Uterus stem 

 median, with 8 to 10 richly branched lateral branches. Gravid 

 segments 4.9 mm. long by 4.2 mm. broad anteriorly, posteriorly 

 4.7 mm. broad, and at opening of genital pore 4.8 mm. broad. 1 



Embryophore ovoid. Genital pore very salient. 



Synonymy. — Lumbricus latits Tyson 1683 (from the dog) ; 

 T. canina Bloch (part.) 1782; T. canina solium Werner 1782; 

 T. canina Carlisle 1793; T. serrata Goeze 1782; AlyschnintJius 

 serratus Zeder 1800; Halysis serrata Zeder 1803 (not T. serrata 

 Rosa 1794; not T. serrata Roll 1853; not T. serrata [from Cyst- 

 icercus tenuicollis] Kuchenmeister 1852). 



Species Taenia serialis. Diagnosis. Taenia: Strobila 45 to 

 y2 cm. in length; head globular, 0.85 to 1.3 mm. in diameter. 



1 Dr. Vital (1874) has reported a case of T. serrata occurring in man. 

 The specimen was found in company with a specimen of T. solium in the 

 intestine of a young girl at the Military hospital at Constantine (Algiers). 



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