BaiRSTOW : ICHNEUMONID^. 



165 



first-rate quality ; let it be of such a character that it will last a 

 lifetime, and be satisfied that the manufacturer is up to this sort 

 of thing. What can be more annoying, after expending several 

 pounds upon a cabinet, after using every endeavour to place our 

 insects in good and scientific array, and after working hard and long, 

 to find a great big crack on the outside of the case, gradually but 

 most surely widening — a consequence of inferior workmanship or of 

 badly-seasoned wood 1 Again, consign the cabinet to the care of an 

 " old hand." My own is made up of cases book-shaped, bought at 

 intervals until the whole of the order taken up is represented either by 

 insects themselves or by names. The book shape I prefer on account 

 of its being a superior preventative against dust, contrasted with 

 drawers which lay flat in the cabinet and give more freedom of 

 access for the dust to accumulate. I may be possessed of somewhat 

 old-fashioned prejudices, yet notwithstanding all the agitation about 

 the question of mite-destroyers, and the particularly vindictive 

 epithets applied to the use of camphor, I have still a lingering regard 

 for, if not belief in, the efficacy of that estimable commodity. If it 

 does no good, it can certainly do but little harm. When used, a small 

 r^ceptack or incision should be made in some portion of the case, to 

 prevent the crystals from tumbling amongst the insects, and causing 

 demolition or accidents. Whether a ridiculous preventive of these 

 little Acari or otherwise, it is a fact that my own specimens have not 

 been extensively victimised, and it is equally a fact that I have used 

 no other " destroyer " ; but failing camphor (as I am well aware of 

 the existence of powerful objections), corrosive sublimate and benzo- 

 line are very good. Let the insects be numbered respectively in the 

 cabinet, and a book kept to correspond, with all necessary particulars, 

 adjacent. Marshall's catalogue, rebound with interleaves, answers all 

 requirements. 



CHAPTER V. — LITERATURE. 



One of the greatest difficulties one has to contend with in the study 

 of parasitic hymenoptera is exposed in this fact — the literature is 

 scanty and mostly foreign. Of late years, however, the number of 

 books has been largely and efficiently augmented, and I believe several 

 works on this subject are at this moment in course of publication. To 

 the student two things are altogether indispensable — a good corres- 

 ponding authority, and a British catalogue of known species. Of the 

 latter no better is extant than the one published by Eev. T, A. 

 Marshall (a work already alluded to), which will serve as an excellent 



