THE AGRICULTURAL PESTS OF INDIA. 67 



Hsemopsis. Horse leech is a name applied to Hsem- 

 opsis sauguisuga, and to a species of Aulostomum. The 

 latter is voracious ; they feed on all creatures. Hsemopsis 

 sanguisuga, Moq., is met with in Sweden, in the south of 

 Spain, in Portugal, and in Turkey. It is very common 

 in the north of Africa, and is one of the main causes of 

 disease in the animals of Algeria. It has feeble jaws, 

 and can only penetrate mucous membranes. Hence the 

 necessity for it to introduce itself into the natural cavities 

 of oxen, horses, and other herbivora, camels, mules ; and 

 into the mouth, pharynx, nasal fossae, and trachea of man 

 when drinking water. There are three principal varieties 

 of leeches employed medicinally in France. These are 

 1st, the grey leech; 2nd, the green leech; 3rd, the 

 dragon leech. The leeches in the damp climate of Assam 

 cause much injury to travellers. They are small, and 

 adhere to the legs in numbers, causing loss of blood and 

 ulcers. 



Land leeches of Ceylon are about an inch in length, 

 and as fine as a knitting needle, but capable of distention 

 to the size of a quill. A closely-woven cloth is needed 

 to prevent their attack. The wound which they inflict 

 is on the more tender and less exposed parts of the body, 

 and on the fetlocks of horses; and the hill leech of the 

 Sikkim streams is no less inimical. 



Haltica has a species in Bengal very similar to the 

 turnip-fly or turnip flea-beetle of Europe, H. nemorum. 

 It feeds on the young leaves and flower-buds of the 

 mustard. 



