30 
Cvsticercus: Cysticercus bovis, a spherical to elliptical 7.5 to 10 mm. long by 3 to 5.5 
mm. broad, whitish to gray with small yellow spot due to the invaginated head; no 
hooks present; the bladder contains but little fluid. This stage requires about 3 to 6 
weeks for its development from the onchosphere. 
Habitat. — Adult known only for man. Cysticercus found in muscles, especially 
ongue and masseters, of cattle ( Bos taurus ); also reported for Rocky Mountain 
“antelope” ( Antilocapra americana), giraffe ( Giraffa Camelopardalis )', and lama 
(Auchenici llama). 
Geographic distribution. — More or less cosmopolitan. 
Special medical significance.— The most common of the large 
tapeworms, except in certain districts where the broad tapeworm 
Fig. 33. — Gravid segment of beef-measle tapeworm ( Tsenia saginata), showing lateral branches of 
the uterus. Enlarged. (After Stiles, 1898a, 77, fig. 73.) 
Fig. 34. — Egg of beef-measle tapeworm (Tsenia saginata), with thick eggshell (embryophore), 
containing the six-hooked embryo (onchosphere), enlarged. (After Leuckart.) 
abounds. It is not so dangerous as T. solium , as there is no danger of 
autoinfection with cysticercosis (see p. 68); anemia is more likely to 
develop with this species than with T. solium , but less likely than with 
Dihothriocephalus lotus / it is more difficult to expell than are the 
other large species. 
Prevention. — Meat inspection; cooking of beef, especially of 
tongue and masseter muscles; cold storage of beef for 21 days after 
killing. A person with this tapeworm should never defecate in fields 
used for pasturing cattle. 
Subspecies and variations. — Occasionally variations, monstrosi- 
ties, and pathological specimens of this species have been found and 
Tsenia inermis fenestrata Maggiora, 1891; T. perforata Maggiora, 1891; T. algeriana 
Pepper, 1894; T. algeriensis Braun, 1894a. 
Bibliography. — For zoological discussion see Leuckart, 1880, 513-616, figs. 237- 
273; for medical literature see Stiles & Hassall, Index-Catalogue of Medical and 
Veterinary Zoology, 
9- Synonyms. -^Cysticercus tseniee mediocanellatse Leuckart, 1863; C. bovis Cobbold, 
1866a; C, inermis Davaine, 1877a; C. teenies saginatee Leuckart, 1880; C. “ cellalosx” 
Ward, 1895; Cysticerkus bovis (Cobbold, 1866) Schneidemuehl, 1896; Cysticerkus tseniee 
saginatee (Leuckart) Schneidemuehl, 18961 
