A. M. ALT80N 195 



bored down and towards the centre of the piece, or if in a vessel at either 

 end it bored down and turned on a lower level towards the centre. It 

 is apparent that the rudimentary eyes enable the larvae to remain within 

 the wood. The larva can be said to be negatively heliotropic. 



Summary. 



1. At maturation, the first instar larva commences to feed upon the 

 residual-yolk-mass contained in the anterior part of the egg, remaining 

 within the chorion to do so. It takes three to five days to accomplish 

 this. It sometimes eats a few particles of the walls or contents of the 

 vessel before settling downi to moult. 



2. From seven to ten days after reaching maturity the young larva 

 undergoes an ecdysis and then commences its boring operations in the 

 wood. 



ACKNOW'LEDGMENTS. 



The investigation, of which this paper records part of the results, 

 was suggested by Prof. H. Maxwell-Lefroy, Imperial College of Science, 

 to whom the writer has to express his thanks; and to the Committee of 

 the Scientific and Industrial Research Department, for a grant to carry 

 on the work. 



The writer is also indebted to Dr C. J. Gahan, Keeper of the Depart- 

 ment of Entomology, Nat. Hist. Mus., for identifying specimens of 

 L. brunneus; to Prof. Percy Groom, Imp. Coll. Sci., for identifying the 

 various species of timber used in this work. 



In addition, thanks are due to Dr A. D. Imms, Rothamsted Experi- 

 mental Station, for his advice, and assistance in connection with the 

 publication of this paper; and to Prof. S. MacDougall for his efforts to 

 get the original paper published as a whole. 



REFERENCES. 



Berlese, a. (1909). Gli Insetti. Milan. 



DuGES, E. (1883). Metamorphoses du Lyctus j^ianicoUis Le Conte, Attn. Soc. Ent. 



Belg. Tome xx\' n. pp. 54-58, plate I. 

 Gahan, C. J. (1920). Furniture Beetles, their Life-history and how to check or prevent 



the damage caused by the Worm. Brit. Mus. (Nat. Hist.) Econ. Ser. No. 11. 



London. 

 Henneguy, L. F. (1904). Les Insectes. Paris. 

 Hopkins, A. D. (1909). Contributions toward a Monograph of the Scolytid Beetles. 1. 



The Genus Dendroctomis. Tech. Ser. No. 17, Part 1, U.S. Dept. Agric, Bur. Ent., 



Washington, D.C. 



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