18. A short account of our present knowledge of the 



Cestode Fauna of British India and Ceylon. 



By T. Southwell, A.R.C.Sc. (Lond.), F.L.S., F.Z.S., 



Dy. Director of Fisheries, Bengal, Behar and Orissa ; 



Honorary Assistant, Indian Museum. 



[Presented at the First Indian Science Congress, January 16th, 1914.] 



The Cestoda ate a group of worms commonly known a- 

 Tapeworms. There are about 3,000 species known. They are 

 all parasitic, and the adult forms invariably live in the intes- 

 tine of the animals infected. They are introduced into carnivo- 

 rous animals by their prey, and into herbivorous animals by 

 means of water and plants. 



Besides being of considerable scientific importance, they 

 are a group of animals not entirely devoid of human interest. 

 The orient pearl of Ceylon is, in reality a sarcophagus laid 

 round the dead remains of a cestode larva. 



It is reported that in Abyssinia, owing to the practice of 

 eating raw beef, every human individual, whether male or 

 female, is infected with worms from the fourth or fifth year of 

 age. The same remark is, to a great extent, true of the Esqui- 

 maux, the Buratis, and of the late American slaves. Taeniasis, 

 or Taenia helminthosis, is very common in Germany. In India 

 human infection is much rarer, owing to the fact that the flesh 

 of animals is not extensively eaten. Indian animals generally . 

 are, however, usually heavily infected, particularly sheep, 

 goat and poultry. 



The range in size within the group Cestoda is remarkable. 

 Echinococcus granulosus (Batsch, 1786), Rudolphi 1805, a worm 

 inhabiting the intestines of the dog and other similar animals, 

 rarely measures more than 1 to 2 mm. in length, whilst Taenia 

 saginata, Goeze, 1782, a human parasite common in Europe, 

 occasionally attains a length of 10 metres (over 33 feet). 



As all adult members of the group live in the intestinal 

 avity, they are in every case provided with hooks or suckers, 

 or both, to enable them to attach themselves to their host 

 From this head, a chain of segments or proglottides is produced. 

 These, as they mature, may drop off singly or in clusters. In 

 most cases each segment is hermaphrodite and contains a single 

 set of male and female reproductive organs. 



In the genus Dioicocestus , Fuhrmann, 1900, recorded from a 

 stork (Plegadis guarauna), and a diver (Colymbus dominicus), 

 the entire strobila is either male or female. 



Beddard has recently recorded (P.Z.S., London, December, 



