568 



]\rATTSsoN ]\Iarn (L). Margborrcns Kronskadegorelse och dess 

 Inverkan pa Tallens Tillvaxt. [The Crown Injury done by 

 Myelophilns pinipcrda and its Influence on the Growth of the 

 Pine.] — Meded. Stat. Skogsforsuksanst., Stockholm, xviii, no. 1-2, 

 1921, pp. 81-101, 2 charts. (With a Summary in German.) 



The investigations reported here on the influence of Myelophilus 

 pinipcrda on the growth of the pine were made in 1916. Details of 

 the method of estimating the amount of injury caused are given, the 

 conclusions being that the amount of increase in diameter of the tnmk 

 is reduced in direct proportion to the injury. The reduction of the 

 increase in the growth of the trunk — as expressed by the area of a 

 horizontal section — is greater than the reduction of the assimilating 

 portion of the tree [i.e., the needles and young shoots], but it is not 

 so great as to make the reduction in the increase of the radius, when 

 expressed in percentages, equal to the reduction in the assimilating 

 portion. 



RoDWAY (J.). Cane Borers in 1879. Past Efforts of the R.A. «& C. 

 Society. — Timckri : J I. R. Agric. & Comin. Soc. British Guiana, 

 Demerara, vii, 3rd Ser., August 1921, pp. 47-60. 



The history of the occurrence of borers in sugar-cane prior to 1879 

 is reviewed, and many records of resolutions passed and work under- 

 taken in that 3'ear are quoted. The borers in question were two 

 weevils, one large and one small, and a moth. Castnia liens had 

 apparently not appeared in 1879 ; it was considered a new pest about 

 1893. 



Skaife (S. H.). On Braida caeca, Nitzsch, a Dipterous Parasite of 



the Honey Bee. — Trans. R. Soc. S. Africa, Cape Toivn, x, pt. 1, 

 30th August 1921, pp. 41-48, 11 figs. 



Braula caeca, Nitzsch, is a common parasite of the honey bee in 

 Africa and elsewhere. It is not pupiparous as was previously thought. 

 The eggs are laid on the brood combs in the hives. The larvae make 

 their way into the cells containing young bee larvae and feed side by 

 side with them on the same food. They also pupate beside the bee 

 pupae, but emerge before the latter and immediately make their way 

 on to the body of their host. The adults apparently feed on honey. 

 These insects rarely become abundant in strong hives, but in weak 

 colonies there is hardly an individual bee to be found without one or 

 more of these parasites. 



I 



Barbey (A.). Contribution a 1 'Etude des Cerambycides xylophages, 



Aegosoma scabricorne, Scot?.— Bull. Soc. Vaiid. Sci. Nat. Lau- 

 sanne, liv, no. 200, 16th September 1921, p. 26. 



The Cerambycid, Aegosoma scabricorne. Scop., has been recorded 

 from many trees, especially limes. The eggs are laid in decomposing 

 wood, and the larval stage lasts from two to three years, during which 

 period winding galleries are bored and miore or less filled with saw- 

 dust. Pupation occurs in June, and the adults emerge three weeks 

 later. Woodpeckers are among the chief natural enemies, but they 

 are imable to reduce the pest materia Ih' as hundreds of borers may be 

 found in one trunk. 



