PRESERVATION OP ENTOMOLOGICAL SPECIMENS. 135 



XVII. Note on the Collection and Preservation of Entomological 

 Specimens, with a Description of the Methods to he employed 

 in the Study of Life- Histories of Insects.'^ By E. P. Stebbing, 

 F.L.S., F.E.S., Instructor in Entomology at the Forest 

 School, Dehra Dun, India. 



General Remarks. 



During the past few years I have been often asked how insects 

 should be killed and preserved, and how packed when it is 

 required to send them away for identification purposes. The 

 question has also been put, " How shall we study the life- 

 histories of insect pests?" I propose giving here information 

 which will, I trust, enable those who wish to work at this 

 important branch of Zoology, to do so with profit to themselves 

 and to the advancement of our knowledge of the subject. To the 

 practical Forest Officer the study of the millions of insect enemies 

 which annually commit depredations in his forests should be one 

 not only of interest to himself, but also of the very first im- 

 portance in carrying out successfully the work entrusted to his 

 care. It is no more possible for us to prescribe remedies, or to 

 even say whether such are practicable or otherwise, until we 

 know the life-history of a pest, than it is possible for a medical 

 man to physic his patient until he has diagnosed the complaint 

 from which he is suffering. The opinion is held by many that 

 perfectly healthy trees in a forest are never killed by insects. 

 Under normal conditions this may be admitted. That a giant 

 of the forest, one that has resisted the storms of a century, should 

 succumb to the attacks of an insect, countless millions of which 

 would be required to equal it in bulk, seems almost absurd ; yet 

 it is nevertheless true, though not, as a rule, quite so literally as 

 it reads. Most of our forest trees support an immense insect 

 population, but it does not necessarily follow that they will show 

 ill-effects from it. Given a perfectly healthy tree, it will bring 

 to maturity a host of feeders upon its foliage, upon the smaller 

 shoots, in the injured or broken twigs or branches, in its fruit, 

 and even in its woody tissue. Comparatively few borers or other 



1 The hints contained in this note, thongh written for the use of Indian 

 foresters, will be found equally useful by their British brethren. It is re- 

 printed from the pamj)hlet issued by the Government of India. — Hon. Ed. 



