Plant Sanitation, 



120 



[August, 1910. 



sporadically in the neighbourhood, 

 it would be advisable for superin- 

 tendents of tea estates in the affect- 

 ed district to keep a tin of the 

 insecticide ready for immediate use. 

 A stitch in time will (in such a case) 

 save ninety times nine. 



In the accompanying plate, the 

 left-hand figure shows a section of 

 infested Oastilloa branch, and the 

 right-hand figureatea branch thickly 

 encrusted by the pest, both about 

 3/5ths natural size. Between them is 

 a drawing of a single insect magni- 

 fied about six times. 



To Protect Rubber Trees 

 Against Rats. 

 Various applications have been 

 tried, with but partial success, to 

 safeguard young rubber trees against 

 the attacks of rats and porcupines. 

 The following extract, from "The 

 Year-book of the Department of 

 Agriculture" (U.S. A), may possibly 

 provide a useful remedy :— 



"During the last year the lime- 

 and-sulphur wash, which for a num- 

 ber of years has been employed to 

 prevent damage to t^ees by the San 

 Jose scale, was tried with great suc- 

 cess in several localities as a pro- 

 tection for orchard trees against 

 the attacks of rabbits. The remedy 

 is cheap, and, as a rule, a single 

 treatment in the fall appears to pro- 

 tect trees for the entire winter," 



The lime and sulphur mixture may 

 be prepared by boiling together 3 

 lbs. of Quicklime, 3 lbs. of Flowers 

 of Sulphur, and 6 gallons of water, 

 until the amount of liquid is reduced 

 to 2 gallons. For spraying the foli- 

 age of plants, this mixture is diluted 

 with 100 parts of water, but as a 

 protection against rats and porcu- 

 pines, it should be applied as a 

 paint of about the density of white- 

 wash, 



Root Gall-worm on Tea. 

 Another case of Root Gall-worm 

 on Tea seedlings has been reported 

 from the Badulla district. A pre- 

 vious case was described in this 

 Journal, July, 1909, p. 35, and August, 

 1909, p. 136. A plate showing the 

 a ppearance of the infested roots is 

 given as a frontispiece to the Novem - 

 ber number of the same year. 



African Snail (Achatina (?) fulica). 

 Nat. size. 



Introduction of an African Snail. 



I have received, through the Assistant 

 Government Agent of Kalutara, specimens 

 of a gigantic snail which is reported to be 

 over-running some villages in the Beruwal- 

 badda of the Kalutara district. They are 

 reported to " feed upon vegetation and the 

 bark of trees, and to be a dangerous pest." 



The snail proves to be a species of Acha- 

 tina, a native of East Africa, whenco it was 

 accidentally introduced into Mauritius and 

 later into India, where it has established 

 itself in the town and neighbourhood of 

 Calcutta. The species appears to naturalize 

 itself readily in any tropical country, and 

 to increase very rapidly. 



It is a giant of its kind. Some of the speci- 

 mens from Kalutara have shells five inches 

 in length. They are of an elongated spiral 

 form, pink at the apex (where the 

 outer akin has been worn off), the 



