CiiAr. v.] PARASITIC WORMS. 245 



which and the disc numerous large fleshy cirri li of a 

 bright crimson colour project downwards, giving the 

 creature a remarkable aspect. No description of it, so 

 far as I am aware has appeared in any systematic work 

 on zoology. 



Sea Slugs. — There are a few species of Ilolothimw, of 

 which the trepang is the best known example. It is 

 largely coUected in the Gulf of Manaar, and dried hi the 

 sun to prepare it for export to China. A good descrip- 

 tion and figiu-e of it are still desiderata. 



Parasitic Woi^nis. — Of these entozoa, the Filaria me- 

 dinensis, or guinea worm, Avhich burrows in the cellular 

 tissue under the sldn, is well known in the north of 

 the island, but rarely found in the damper districts 

 of the south and west. In Ceylon, as elsewhere, the 

 natives attribute its occurrence to drinking the waters 

 of particular wells ; but this behef is inconsistent with 

 the fact that its lodgment in the human body is almost 

 always effected just above the ankle, which shows that 

 the minute parasites are transferred to the skin of the 

 leg from the moist vegetation bordering the footpaths 

 leading to weUs. The creatures are at this period 

 minute, and the process of insinuation is painless and 

 imperceptible. It is only when they attain to considerable 

 size, a foot or more in length, that the operation of ex- 

 tracting them is resorted to, when exercise may have 

 given rise to inconvenience and inflammation. 



Planar ia. — In the journal above alluded to. Dr. Ke- 

 laart has given descriptions of fifteen species of planaria, 

 and four of a new genus, instituted by him for the recep- 

 tion of those differing from the normal kinds by some 

 peculiarities which they exhibit in common. At Point 

 Pedro, Mr. Edgar Layard met with one on the bark of 

 trees, after heavy rain, which would appear to belong to 

 the subgenus geoplana} 



' " A curious species, wliicli is of i a peculiarly shaped tail, half-moon^ 

 a light brown above, wliite mider- shaped, in ftict^ like a grocer's cheese 

 neatli ; very broad aud thin, and has | Iniife." 



It 3 



