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PROCEEDIXGS OF THE THIRD ENTOMOLOGICAL MEETING 



Mr. Ramakiishna 



Ayyar. 



In some places shells of water-snails are tied at the end of a rope, 

 and, by moving the rope, a jingling sound is produced, and this sounds 

 like the noise of water coming in and the crabs come out of their holes 

 and are then hooked. I have seen this done several times. 



In some places they grind together two stones, with sand in between 

 them, and the crabs think it is raining and come out of their holes. 



Crabs are doing damage in South India. As a rule the crabs are 

 carnivorous but the young ones probably cannot get the desired food 

 and so they take to paddy seedlings. We have actually seen them 

 cutting paddy and after dissection found paddy in their stomachs. 

 The adults live in holes and these holes are not as Mr. Ghosh described. 

 They are winding about and at the bottom of the hole is a little water. 



We tried the following bait. We made small balls of Paris Green, 

 molasses and bran and placed them at the mouths of the burrows. At 

 the time there was no crop in the field. This worked very well for two 

 or three days and we killed thirty or forty crabs out of a hundred holes. 

 They did eat the bait as was proved by the examination of their stomachs. 

 But after two days they did not eat any. We do not know why. It 

 is only the seedling that is damaged and if this is protected for a week 

 or ten days there is no more trouble. We used a wire-gauze screen 

 at one place and it kept them out for sometime, but it is not possible 

 to do this over large areas. In lands which are irrigated they are bad. 

 They hibernate as adults and breed in June or July, i.e., in the early 

 Rains. 



How big are the balls you use 1 



As big as a marble, half an inch or so in diameter. 



Crabs in many parts do not damage the paddy plants directly but 

 are harmful indirectly as they make holes in the himds and let water 

 out. In one field there were five hundred holes in a bund. 



We had a similar complaint from the Salt Department. Holes 

 were made and water drawn off. 



In Egypt a Paratelphusa ? bores holes in dams and lets the water 

 out. 



We tried crab-pots. They are deep pots and are kept with their 

 mouth just above the water level and we keep in them some fried things. 

 Crabs drop down in them and they are not able to get out. 



In our parts crabs do damage to paddy in the following way. During 

 the summer the whole field is under water and then we make bunds 

 and draw off the water. The crabs make holes and the water comes 

 in again. 



Why the damage is not visible is, I believe, due to the fact that 

 in most places handfuls of seedlings are put in one place and if two 



