THE ENTOMOLOGIST. 
No. 90.] MAY, MDCCCLXXI. [Price 6d. 
Answers to Correspondents. 
[I have found so much time occupied in writing a separate 
letter to every querist, that I have at last determined to 
resort to this plan of answering queries en masse. None of 
the letters answered in this number of the ‘ Entomologist’ 
were intended for publication, and, therefore, I do not give 
the names of my correspondents, but I will gladly do so 
whenever requested. In all cases I propose to add any 
collateral information I may possess and can compress 
into a few lines, even although not definitely required 
by my correspondent.—Hdward Newman. | 
Mr. Doubleday’s Health.— Very many inquiries have 
reached me respecting my friend H. Doubleday, who has 
been absent from home for four months in consequence of 
illness. Iam now able to hand my readers the agreeable 
information that his health has improved, and he has returned 
to his old residence at Epping. I trust that his life may be 
prolonged for some years, and I hope he will be able to 
pursue his favourite studies in Natural History. Should this 
be the case I have no doubt that his zeal in assisting others 
will be as great as ever; but his medical adviser wishes him 
to abstain from much exertion at present. 
Sirex Juvencus.—The mummy-like objects in the deal are 
specimens of Sirex Juvencus, a timber-eating insect of the 
hymenopterous order Phytophaga: the extraordinary differ- 
ence amongst them in size is not specific; it is usual for 
timber-feeding insects to vary in this remarkable manner; 
the difference in colour is sexual; those with yellow bodies 
and black hind legs are males; those with steel-blue bodies 
and yellow hind legs are females. Nevertheless, there appear 
to be three species inhabiting this country, and each confines 
itself to a single species of fir; these are:—1. Lavricis, with 
black antennez, and a black tip to the abdomen in the male: 
VOL, V. T 
