Fig. 241.—Mature seg­ment of Tænia sa­gi­nata, G., with dis­tend­ed uterus. 2/1.

Syn.: Tænia solium, L., 1767 (pro parte); Tænia cucurbitina, Pallas, 1781 (p.p.); Tænia inermis, Brera, 1802. Moquin-Tandon, 1860; Tænia dentata, Nicolai, 1830; Tænia lata, Pruner, 1847; Bothriocephalis tropicus, Schmidtmuller, 1847; Tænia mediocanellata, Küchenmeister, 1855; Tænia zittavensis, Küchenmeister, 1855; Tænia tropica, Moquin-Tandon, 1860; Tænia (Cystotænia) mediocanellata, Leuckart, 1863.

Fig. 242.—Ceph­al­ic end of Tænia sa­gi­nata in the con­tract­ed con­di­tion. 8/1.

The length of the entire tapeworm averages 4 to 8 to 10 m. and more, even up to 36 m. According to Bérenger-Feraud it attains a length of 74 m. (?) The head is cubical in shape, 1·5 to 2 mm. in diameter; the suckers are hemispherical (0·8 mm.) and are frequently pigmented; there is a sucker-like organ in place of the rostellum, and this also is frequently pigmented. The neck is moderately long and about half the breadth of the head; the proglottids, the number of which averages more than 1,000, gradually increase in size; the mature detached segments are shaped exactly like pumpkin-seeds, and are about 16 to 20 mm. in length and 4 to 7 mm. in breadth. The genital pores alternate irregularly and are situated somewhat behind the middle of the lateral margin. There are twenty to thirty-five lateral branches at each side of the median trunk of the uterus, and these again ramify. The eggs are more or less globular, the egg-shell frequently remains intact and carries one or two filaments; the embryonal shell (embryophore) is thick, radially striated, is transparent and oval; it is 30 µ to 40 µ in length, and 20 µ to 30 µ in breadth. Several segments simultaneously are usually passed spontaneously with defæcation.

Malformations are not uncommon, and resemble those of Tænia solium; a triangular form has been termed T. capensis by Küchenmeister, and T. lophosoma by Cobbold, names that naturally possess as little value as does the term T. fenestrata for fenestrated specimens. Moreover, T. solium, var. abietina, Weinld., 1858, which was evacuated by an Indian, was probably a T. saginata with somewhat close uterine branches. It is regarded by Stiles and Goldberger as a doubtful subspecies.