CESTODES 



517 



corresponds to the male sexual organs. The intermediate hosts are, according 

 to Grassi, small insects, such as akis spinoza, anisolabis annulipes, asopia 

 farinalis, scaurus striatus, by the accidental ingestion of which man may also 

 become infected. These observations were confirmed by infection experiments 

 in man and in rats. The parasite has been so far found only seven times in 

 man, and almost exclusively in children. 

 Quite as rare is the 



Tenia madagascariensis, Davaine, 1869. 



This tape-worm is about 25-30 cm. long, with about 660-700 segments. 

 The head is supplied with four large, circular suctorial discs, and a rostellum 

 with a row of 90 peculiarly formed booklets. The mature proglottides are 

 3 mm. long, 1.4 mm. broad. The sexual openings are situated on one side. 

 Each proglottid contains 180-150 small round ova. We are ignorant of the 

 exact development of the parasite and only know that species similar to this 

 tenia dwell in birds. Only five cases of this kind have been observed so far 

 in the tropics, among them one in British Guiana (by Daniels). 



It appears to be very doubtful whether the tenia marginata, Balsch, 1786, 

 the tenia Serrata, Goeze, 1782, and the tenia crassicollis Eudolphi, 1810, or 

 their cystieerces, have been observed in man, but five unknown teniae occurring 

 in man have been reported, and have been called the 



Tenia confusa, Ward, 1896. 



Ward, in a preliminary report, has described a tenia found in man. Its 

 length was about five meters. The end proglottides measured 27-35 mm., the 

 breadth 3.5-5 mm. This tenia is considerably more slender than the tenia 

 saginata. The head has four suctorial discs, and a retractile rostellum with 

 six or seven rows of small hooks, those in the front row being the largest. 



Fig. 38. 



Fig. 42. 



Fig. 41. 



Fig. 39. Fig. 40. 



Figs. 38-42. — Tenia confusa Ward. (After Guyer.) 

 Fig. 38, a, b, c, d, Chain of proglottides. Fig. 39, a and h, Mature proglottides. Fig. 40, Female 

 sexual organs. Fig. 41, Male sexual organs. Fig. 42, Ovum of the tema confusa. 



The proglottid-chain is distinguished from tenia solium and tenia saginata 

 by continuous longitudinal musculature, by the presence of a vesicula seminalis 



