232 



THE ANIMAL PARASITES OF MAN 



i. Davainea madagascariensis, Davaine, 1869. 

 Syn. : Tcenia madagascariensis , Dav. ; Tcenia demeranensis , Daniels, 1895. 



This worm measures 25 30 cm. in length ; the head has four 

 large round suckers; the rostellum has 90 hooks (0*018 mm. in 

 length) : there are 500 to 700 segments, of which the last hundred are 

 filled with eggs and form half of the entire worm. The segments, 

 when mature, measure 2 mm. in length by 1-4 mm. in breadth ; 

 genital pores on the same lateral border : about 50 testes ; the uterus 

 consists of a number of loops, which at each side are rolled up 

 into ah almost spherical ball ; when filled with eggs the con- 

 volutions unwind, permeate the segment and then lose their 

 wall ; the eggs lying free in the parenchyma 

 become finally surrounded, one, or several together, 

 by proliferating parenchymatous cells ; this is how 

 the 300 to 400 ovarian vesicles, taking up the 

 entire mature segment, are formed. The globular 

 oncosphere (o'OoS mm.) is surrounded by two per- 

 fectly transparent shells ; the external shell ter- 

 minates in two pointed processes. 



Davainea madagascariensis has hitherto been 

 found in man only. Davaine described this species 

 from fragments sent to him from Mayotte 

 (Comores), and which were found in two Creole 

 children, Chevreau observed four cases in Porte- 

 Louis (Island of Mauritius), likewise in children ; 

 Leuckart received the first perfect specimen ; it 

 was obtained from a three-year-old boy in Bang- 



kok ' the son of a Danish ca P tain ; Daniels > a t 



the post mortem of an adult native of George 

 Town, Guiana, found two specimens (Tania 

 demerariensis), and finally Blanchard describes 

 another perfect specimen which was in Davaine's 

 collection of helminths in Paris, and which was obtained from a 

 little girl three years old, of Nossi-Be (Madagascar). The inter- 

 mediary host is unknown. 



LITERATURE. 



GRENET and DAVAINE. Not. sur une nouv. esp. de Taenia rec. a Mayotte. (Mem. 



soc. biol., Paris, 1869 [5]> i-> P- 2 33 ', Arch, de med. nav., 1870, xiii., p. 134.) 



CHEVREAU, P. Le T. madagasc. (Bull. soc. med. de 1'ile Maurice, 1891, ix., 



P- 523.) 



BLANCHARD, P. Note sur quelq. vers par. de rhomme. (C. R. soc. biol., Paris, 

 1891 [9], iii., p. 604.) 



fallen off. 



