185 



of India, including the Himalayas; a list of localities is given. There 

 is no doubt that it was introduced on .imported apple stocks. In 

 view of the fact that the elm is the primary host, attention is drawn 

 to the need for examining any elms near apple orchards. 



Spraying against the aerial form and grafting against the root 

 form are the measures mentioned. 



d'EmmerezdeCharmoy(D.). Report on the Work of the Division 

 of Biology. — Mauritius: Ann. Rept. Dept. Agric. 1919, 1920, 

 pp. 12-13. [Received 14th February 1921.] 



A fresh infestation of Lachnosterna [Phytalus) smithi was discovered, 

 against which remedial measures are in progress. During the year 

 69,102,233 beetles were destroyed, the number being considerably 

 smaller than in the previous year ; the parasite, Tiphia parallela, is 

 largely responsible for this. Other pests recorded are Oryctes tarandus 

 on sugar-cane and a gall insect on mango. 



The Mango-tree Borer (Violin) {Batocera ruhus).— Mauritius : Dept. 

 Agric, Reduit, Leaflet 10, 23rd Julv 1918, 2 pp., 3 figs. 

 [Received 14th February 1921.] 



The Longicorn beetle, Batocera ruhus, known locally as the mango- 

 tree borer, or violin on account of the peculiar sound it produces 

 when irritated, does considerable damage to mango and other trees 

 in Mauritius, and its partiality for kapok appears to be responsible for 

 the discontinuance of the cultivation of that useful tree in the Colony. 



Brief notes' on the structure of the adults and larvae" are given. 

 The eggs are deposited singly in cracks in the bark, in which the 

 young larvae remain for the greater part of their life. Their mines 

 are irregular, narrow and sinuous. When they are 40-45 mm. long, 

 they bore large circular galleries in the wood ; when these finally 

 reach the outer surface immediately under the bark, the larvae pupate. 

 Though concealed in the trunk and branches, their presence is be- 

 trayed by the brownish fluid trickling from the wound. When they 

 are under the bark the tree can be saved, but when they are in the 

 wood there is no practical means of destroying them. There is ground 

 for believing that the life of the larva is not less than one 5^ear. The 

 adults are found all the year round, but more abundantly in summer, 

 at which period the attacks of the larvae are first noticed. 



The beetles may be captured and killed. Trees severely infested 

 with the larvae should be felled and split into pieces and all the larvae 

 destroyed. Logs should not be left on the ground. If a tree is slightly 

 infested the larvae may be cut out. A trained man can in less than 

 a day clear a tree of all its larvae. 



This pest also occurs in Madagascar, Reunion and elsewhere. 



Departmental Activities, November, 1920 : Entomology.—//. Dept. 

 Agric, Union S. Africa. Pretoria, ii, no. 1, January 1921, pp. 

 14-16. 



An arrangement has been made to have codling moth larvae collected 

 m autumn in Italy and sent to South Africa, with the view of intro- 

 ducing the Italian parasites of this pest. An attempt is also being 

 made to introduce Aphelinus mali from North America, where it 



