319 



Bruch (C). Captura de Cerambicidos. — Physis, Buenos Aires, iv, no. 

 17, 20th December 1918, 354-355, 1 fig. [Received 28th May 

 1919.] 



In view of the quantities of wood and timber that have been brought 

 down from the northern forests, many Lonoicorn beetles have been intro- 

 duced during the last few years that were formerly unknown or very rare 

 in the Pro^dnce of Buenos Aires, Argentina. Hamaticherus lacordairei 

 Gah.,for example, is frequently observed in the heart of the capital, 

 while other introduced species characteristic of the northern provinces 

 are Calocomus desmaresti, Guer., 3Iacroeme priapica, Thorns., Chlorida 

 f estiva, L., Eburia sordida, Burm.,. Orion patagonus, Guer., Neoclytus 

 famelicus, Burm., Trachyderes sidcatus, Burm., and Basipterus 

 castaneipennis, Thorns. A more interesting discovery is that of 

 Phoracantha semipunctata, ¥., a native of Australia. The first 

 individual of this species was captured in Belgrano in January 1917, 

 ^ince when several have been taken in various localities. It has been 

 previously recorded from Brazil, and is now perhaps acclimatised 

 on some native plant and probably also attacks Eucalyptus, which 

 has been introduced from Australia. 



Bertrand (G.) & Rosenblatt (M.). Action toxique compar6e de 

 quelques Substances volatiles sur divers Insectes. — C.R. liehdom. 

 Acad. Sci., Paris, clxviii, no. 18, 5th May 1919, 911-913. 



Experiments have been carried out to test the comparative values 

 as insecticides of ordinary anaesthetics, such as ether, chloroform, 

 carbon bisulphide and carbon tetrachloride ; irritants, such as mono- 

 chloracetone and benzyl bromide ; substances at the same time 

 irritating and suffocating, such as nitrochloroform or chlorpicrin ; 

 and simple poisons, such as hydrocyanic acid. These have been 

 tested for the most part on a single species, the caterpillars of Mala- 

 cosoma neustria, L., occurring in large numbers on elms near the 

 laboratory. As far as material permitted, tests were also made on 

 Spdrganothis pilleriana, Polychrosis botrana, a Noctuid, and a sawfly. 



The insects were subjected to the action of known mixtures of air 

 and the poison vapour, in the manner already described [see this Revieiv, 

 Ser. A, vii, p. 285], usually for 10 minutes, though in some cases this 

 has been extended to half an hour or an hour, and the following 

 conclusions were reached: — Ether is not very active; exposure to 

 "5 gm. per litre of air for 10 minutes produces only temporary anaesthesia, 

 one adult larva recovering within a quarter of an hour, and two others 

 after half an hour, all of them spinning their cocoons 4, 5 and 7 days 

 later, respectively ; chloroform is rather more active than ether, 

 3 larvae subjected to the above strength for 10 minutes all recovering 

 after 55 minutes, and being alive but rather inactive 2 days later, while 

 a concentration of 5 to 10 mg. per litre effects a slight anaesthesia ; 

 carbon bisulphide is clearly more toxic than either of these, exposure 

 to a strength of "5 gm. per litre for 10 minutes causing 3 larvae to 

 remain motionless and apparently dead for several days, after which 2 

 pupated and the third died ; carbon tetrachloride acts very like chloro- 

 form, but larger doses are always necessary to obtain the same effects ; 

 monochloracetone is much more active than the preceding substances. 



