102 



shoots and though not actually killing the plants preventing them 

 from bearing. 



The pest is one of the moth caterpillars called Nettle worms, 

 of the group of Limacodidx. It is an inch long and very thick, 

 and slug-shaped the back all except its head is bluish white thickly 

 covered with radiating tufts of sharp blue or white species, the 

 head and belly smooth and dirty yellow. At the tail there is a bare 

 patch yellowish in colour with 4 black velvety spots in a transverse 

 row. The spines on its back are apparently poisonous as like all 

 this set of caterpillars it can sting with them 



I failed to raise any of the moths of this caterpillar as they were 

 too much injured in travelling. It is a very common animal and 

 may often be seen on Soursop and other trees, but I have never 

 seen it in large quantities. The simplest way of dealing with it is 

 handpicking, but as the caterpillar defends itself with its poisonous 

 thorns, it is necessary to remove or kill it with small sticks or 

 pieces of bamboo. Caterpillars are easily wounded and a wound 

 is invariably fatal so that they can be destroyed by merely spearing 

 them with a sharp piece of bamboo. I cannot find that insecticides 

 have been tried on this insect, but as it usually occurs in a some- 

 what scattered manner probably children could quickly destroy 

 them in the manner suggested. 



Some of the allied nettle grubs have done a great deal of harm 

 in Tea estates in Ceylon and India. Mr. Green ( Pests and 

 Blights of the Tea plant) warns planters to look out for and des- 

 troy the preliminary broods to prevent there being a sudden increase 

 in the pest, and suggests the use of arseniate of lead as an insec- 

 ticide sprayed over the leaves. Of course planters will remember 

 that this is poisonous and pepper fruit sprayed with it might be 

 dangerous so that it should not be used when the pepper crop is 

 nearly ripe. 



Editor. 



ON THE PREPARATION OF RUBBER. 



An important paper with this title written by the well known 

 expert Dr. C. O. Weber appears in the India Rubber Journal, 

 Feb. 15, 1904, p. 172. The paper deals with the latex of Castilloa 

 on which Dr. Weber has long been working but also more espe- 

 cially with that of Hevea of which he received large samples 

 brought over in cold storage. He points out that the coagulation 

 of latex in Castilloa is due to the coagulation of the albuminous 

 matter in the latex. The India rubber substance is dissolved in 

 the latex but is emulsified or suspended in it. So that when the 

 albumen is coagulated it brings down with it the rubber. Tin 

 coagulation depends very considerably on the exact nature of the 

 albuminoid contained in the latex as well as the presence of certain 

 inorganic salts. Hence two different kinds of latex of different 

 botanical origin cannot be coagulated equally easily nor even per- 



