234 



at the centre of others. After leaving the lowest disc the seed is con- 

 veyed out of the vertical, cylindrical hot air chamber, enclosing these 

 working parts. A temperature between 53° and 56"^ C. [127-4° and 

 132-8° F.] is the best for disinfection, but results in decreasing the 

 germinating capacity of the seed by about 15 per cent. This decrease 

 is, however, of little importance in view of advantages gained by the 

 destruction of the pest. Another type of this apparatus works with 

 steam instead of hot air. It is suitable for desiccating vegetables and 

 grain, and should be of use in cases of infestation of such products by 

 weevils. 



Carbon bisulphide has proved ineffective against P. gossypiella. 

 The larvae survive fumigation for 48 hours with the usual commercial 

 grade, and it is difficult to obtain the chemical in a pure form. 



BoNDAR (G.). Planta tanifera — Acacia decunens no Brasil. [A 

 tanniferous Plant, A. decunens, in Brazil.] — Bol. Minist. Agric, 

 Ind. & Comm., Rio de Janeiro, x, no. 1, January-February 1921, 

 pp. 95-99, 5 plates. [Received 4th March 1922.] 



Acacia decurrens var. mollissima, which has been introduced into 

 Brazil from Australia, is attacked there by the Cerambycid beetles, 

 Criodion tomentosum, Serv., Coccoderus novempunctus. Germ., and 

 Oncideres impluviata. Germ. 



The presence of C. tomentosum is revealed by swellings, which develop 

 into wounds that exude gum. The adults occur from November to 

 March and oviposit in the bark of the trunk and large branches. The 

 larvae penetrate into the wood and bore upwards in the trunk. The 

 mine may be 19 in. long. The larval stage lasts two years, pupation 

 taking place at the upper end of the gallery. Infestation is easily 

 preventible by clean cultivation, but once the trees are attacked they 

 should be cut down and burnt. 



The female of Coccoderus novempunctus oviposits in the smaller 

 branches, and from these the larva bores into the larger ones and the 

 trunk. When mature, it makes a spiral mine round the branch or 

 trunk near the bark, and the portion above this cut falls to the ground 

 with the larva, which then pupates near the bark. Branches up to 

 six inches in diameter may be cut off in this manner. Some native 

 Leguminosae are also attacked. Development requires two years. 

 The fallen branches should be collected and the larvae within them 

 killed. 



The larva of Oncideres impluviata lives in recently dead wood, and 

 to obtain such material the female cuts off the branches and stems of 

 various Leguminous plants from one-fifth to one inch in diameter, 

 and then oviposits in the amputated portions. The larval stage lasts 

 from seven to eight months, and the adult emerges from the rotten 

 wood and renews the attack from December to mid-February. This 

 beetle is comparatively rare, but in one case all the trees of A . 

 decurrens in a plantation were destroyed. The pest can be got rid of 

 by collecting and destroying the fallen branches from April to July. 



MoRSTATT (H.). Die BekampJung des roten Kapselwurms der 

 BaumwoUe. [The Control of the Pink Bollwonn of Cotton.] — 

 Der Tropenpflanzer, Berlin, xxv, no. 1-2, January-February 

 1922, pp. 22-25. 



The rapidity with which Platyedra [Gelechia) gossypiella, Saund., 

 has become one of the most important pests of cotton is reviewed, and 



