170 MEDICAL ZOOLOGY. 



deferent canal. The ovary is a large irregularly lobed mass situated in the 

 jentre of the segment. (Moquin-Tandon.) 



It is calculated that as many as 1200 proglottides may be passed in three 

 mouths. The Taenia is oviparous ; each segment may contain several hun- 

 dred eggs. 



Measurements. 10'-30' long; 4"' wide. 



Habitat. Small intestine of man. 



T. mediocanellata (Unarmed tapeworm), Klichenraeister. Head abruptly 

 truncate at the crown, destitute of rostellum, and consequently also of a 

 hook-apparatus ; furnished with conspicuously large sucking disks, usually 

 surrounded by a great quantity of dark pigment granules giving the head a 

 blackish appearance. Ovary of the same type as in preceding species, but 

 more complicated, presenting nearly double the number of lateral branches, 

 which do not, moreover, branch out so dendritically. The terminal, 360-400 

 joints, may be mature. Joints apt to form monstrosities. 



Measurements. 36'-40'long; 5'" wide. (Kiichenmeister.) 



Habitat. Small intestine of man. 



T. echinococcus, Von Sicbold. Head with pointed proboscis armed with 

 a double row of comparatively large rooted hooks from thirty to forty in 

 number ; the four suckers prominent, and succeeded by an elongation of 

 the segments forming the neck; final segment when mature equalling in 

 length the three anterior ones ; ovary is placed in median line of proglottis, 

 the oviduct having appended to it two distinct yolk glands modified near 

 its outlet into a uterine chamber and receptacle. The genital pore is at the 

 margin of the proglottis below the central line. The male organ consists of 

 numerous sacs communicating with a vas deferens twisted upon itself, which 

 terminates in a constantly protruded penis of large size. 



Measurement. 3'" long. 



Habitat. Small intestine of dog; larval form (hydatids) in man. 



T.acanthotrias, Weinland. Discovered in 1858. Cysticercal form ; three 

 rows of hooks. Known only in its larval form, which was found in muscle 

 of man. (Wyman.) 



T.flavopuncta, Weinland. Proglottis short, with a 'yellowish spot clearly 

 visible to naked eye, situated about the middle of each joint.' Reproductive 

 organs occur on one side only. Known only from its strobile condition. 



Habitat. Intestine of man. 



T. nana, Siebold. Head obtuse, large, and placed on a long, neck-like 

 region. Segments proportionately broader than in other worms. Eggs 

 globular. Known from proglottis- Obtained in considerable quantities from 

 a child who died of meningitis. 



Measurement. 6"' long. 



T. elliptica, Batsch. Head with conical proboscis, armed with several 

 rows of minute hooks. An ovary or testicle upon either side of each seg- 

 ment, opening into a central lateral pore. 



Measurement. 6-8" long. 



