KO. 2258 TAENIOID CE8T0DE8 OF DOGS AND CATS— HALL. 5 



Family TAENIIDAE Ludwig, 1886a. 



/Synonyms. — Taeniaclao Baird, 1853(2; Taeniodea Diesing of Gold- 

 berg, 1855a; Taeniadea Cams, 1863; Teniadae Perrier, 1897a. 



Family diagnosis. — Taenioidea : Rostelliim usually well developed, 

 rarely rudimentary, and usually armed with a double crown of hooks 

 composed of a circlet of large hooks and a circlet of small hooks, the 

 large and small hooks arranged alternately; rarely with a single (?) 

 circlet of hooks or unarmed. Suckers unarmed. Gravid segments 

 longer (that is, along the longitudinal axis of the strobila) than 

 broad (that is, along the transverse axis of the strobila) . A single set 

 of reproductive organs in each segment with the genital pores irregu- 

 larly alternate. Testes numerous. Ovary bilobed, or may be re- 

 garded as two ovaries. Uterus with a median stem and lateral 

 branches and without an opening to the exterior for the escape of the 

 eggs. 



Type-genus. — Taenia Linnaeus, 1758. 



Subfamily Taeniinae Stiles, 1896&. 



Synonyms. — Taeniea Goldberg, 1855a; Cystotaeniae Glaus, 1876; 

 Taenianae Railliet, 1896. 



Subfamily diagnosis. — Taeniidae: Usually large species. Gravid 

 segments usually considerably longer than broad. Scolex with ros- 

 tellum and usually armed with a double crown of hooks, rarely with 

 a single ( ? ) circlet of hooks or unarmed. Genital pores irregularly 

 alternate. Testes usually very numerous, mostly in the lateral por- 

 tions of the median field bordered by the longitudinal excretory 

 canals and to a less extent in the median portion of this field. Ovary, 

 shell-gland, and yolk-gland in the posterior portion of the median 

 field, distal from the head. Uterus with a median stem from which 

 develop lateral branches, the structure suppressing the genital glands, 

 wholly or partly, in gravid segments. Of the four longitudinal ex- 

 cretory canals, usually only the ventral are readily visible in gravid 

 segments. Egg shell thin, with or without filaments, usually disap- 

 pears after a time; embryophore thick and radially striate. Inter- 

 mediate larval stage a bladderworm of the cysticercus, coenurus, or 

 echinococcus type, occurring in herbivorous or omnivorous animals. 

 Adult stage a strobilate worm in carnivora or omnivora. 



Type-genus. — Taenia Linnaeus, 1758a. 



KEY TO THE GENEttA OF TABNIINAH. 



1. Strobila less than 1 centimeter long and composed of a head and 3 segments, 

 only one of the segments being gravid at a time. Lateral uterine branches 

 often quite indistinct. Yolk-gland globular. Larval stage an echinococcus 

 with thick laminated wall, and developing brood capsules containing the 

 larval scolices Echinococcus, p. 56. 



