42 Journal of the Asiatic Society of Bengal. {February, 1912. 
Oligochaeta are rapidly rendering this statement obsolete so 
far as that group is concerned. It may be mentioned here that 
representatives of several families of the essentially marine 
group Polychaeta make their way up the estuaries of the Gan- 
getic delta into water that is practically fresh and hide them- 
selves among freshwater sponges. 
The Indian leeches are as yet little known, but a large 
collection has been made and is now being studied by Mr. W. 
A. Harding, who is preparing a volume on the group in the 
‘* Fauna.” 
The parasitic flat-worms and round-worms that infest the 
fish and other animals of our Indian rivers, lakes and ponds 
are still practically unknown. Mr. T. Southwell, however, 
permits me to state that he has recently found in Indian bony 
fish (Ophiocephalus) adult tape-worms of the genus T etraboth- 
rium. The discovery is an important one, as, with the excep- 
the latter genus from the liver of a Burmese tortoise and has 
recorded the occurrence of Linguatula subtriquetra, a species of 
the same group hitherto only known from America, in a croco- 
dile from the Ganges. 
A small but important group of flat worms named 'Temnoce- 
phaloidea was first recorded from the Indian Empire by the 
late Mr. J. Wood-Mason,’ who, however, identified the species 
he observed incorrectly. The worms of his group live on the 
external surface or in the gill-chamber of freshwater crustacea 
and other aquatic animals in many tropical and sub-tropical 
countries. ey are not parasites but actively predaceous 
animals, using the hosts to which they adhere merely as beasts 
of burden and stalking-horses. Mr. F. H. Gravely has been able 
to prove by an actual comparison of specimens that a species not 
uncommon on freshwater crabs in some parts of Tenasserim 
is identical with one described by Prof. Max Weber+ from 
the Malay Archipelago under the name Temnocephala semperi 

1 Von Linstow, J.A.8.B. (N.S.), II, p. 269 (1906). S 1 
— ee a Sasso of Platanista: J “ $B. 1 Yo : pasa 
arasitology, III, pp. 275, ete. (1910). Th Li raabeli 
course are not worms but degenerate ant Be ire 
’ Ann. Mag. Nat. Hist. (4) xv, p. 336 (1875). 
+ Zool. Ergebnisse in Niederland. Ost-Ind. I, p. 1 (1890). 
