1915-16.] Structure and Life-History of Bracon sp. 
313 
XX. — The Structure and Life-History of Bracon sp. : a Study 
in Parasitism. By James W. Munro, B.Sc. (Agr.) and B.Sc. 
(For.), Board of Agriculture Research Scholar. Communicated 
by Dr R. Stewart MacDougall. (With Two Plates.) 
(Read July 5, 1915. MS. received February 2, 1916.) 
Introductory. 
In July 1913, while collecting the larvae of the large Pine Weevil ( Hylobius 
abietis), I discovered a number of tiny larvae feeding on some of them. 
These I succeeded in rearing, and they proved to be the larvae of a Bracon 
which seemed to be B. hylobii. In July 1914 I recorded my experiments 
and observations.* In this record I stated that my identification of the 
species was based on Ratzeburg’s description.]* All the specimens I 
examined — and I have examined many — agree, for the most part, with 
his description of B. hylobii. In April 1914, specimens were sent for 
determination to Dr Szeplegeti, the authority for the family, in Budapest, 
but so far no reply has been received. 
Bracon hylobii had never previously been recorded in this country. 
In 1911 Dr Stewart MacDougall received from the late Dr Nisbet a 
Braconid, parasitic on Hylobius, but in such a state that determination 
of the species was impossible. It was, however, definitely identified as a 
Braconid, after comparison with specimens in the British Museum. 
The earliest record of B. hylobii I have been able to find is in 
Ratzeburg’s Ichneumonen der Forstinsekten ( loc . cit.), published in 1848. 
He there describes the species, and quotes Nordlinger’s observations on it. 
One other reference is that of Brischke, who includes B. hylobii in his 
list of Ichneumonidae of West and East Prussia.]; Neither of these 
authorities gives any account of the Bracon s life-history. Recently my 
attention has been drawn to a Paper, by Forstmeister Dolles,§ the 
* Annals of Applied Biology , vol. i, No. 2, pp. 170-175. In this Paper the insect was 
named B. hylobii, but as there is some doubt yet, it has been thought better, throughout 
this new Paper, to describe the species as Bracon sp. 
f Ichneumonen der Forstinsekten , Band ii, p. 38. 
f G. A. Brischke, “Die Ichneumonen der Provinzen West- und Ost-Preussen,” Schrift. 
naturfors. Gesell ., Danzig, Neue Folge, 1882, p. 135. 
§ “Der Nutzender Braconiden in forstlichen Haushalte,” Forstlich-Naturwissenschaft- 
lichen Zeitschrift , 1897. 
