964 I'KOCKEDINGS OF THE THIUD ENTOMOLOGICAL MEETING 



insects may be relaxed in twenty-four hours and large ones in two 

 or three days. The process may be hastened by using warm water, 

 over which the insects are suspended or floated on a piece of cork. 

 Care must be taken that the insect is sufficiently softened to permit 

 of easy setting and, conversely, that it is not left in the relaxing-tin so 

 long that it becomes too decomposed. As already noted, relaxed 

 insects are peculiarly liable to " spring " {i.e., the wings fail to 

 retain their positions) if removed, too soon from the setting-board ; 

 extra time on the boards should therefore be given in the case 

 of all relaxed specimens and, in any obstinate cases, the wings 

 may be fixed with a small drop of cement applied to the base of the 

 lower surface of each wing. 



Green insects, especially moths, are very liable to fade when relaxed 

 and should therefore be set when fresh as far as possible. 



Cement, by the way, should also form part of the collector's appara- 

 tus, as it is often requtred for mending broken specimens. Special 

 Insect Cement is prepared, obtainable in small bottles, and only a very 

 minute quantity is required to Be appUed. If it becomes too thick, 

 it may be softened by adding a little vinegar or acetic acid solution. 



Preservation. 

 Assuming that an insect is pinned and labelled and (whether set 

 or not) is ready to be placed in the collection, it still remains to take 

 all necessary precautions to preserve it effectively. To do this it is 

 necessary to keep it free from fungal and animal pests and from the 

 action of light. 



Mould is the worst enemy of insect collections in damp climxtes 

 such as are found in most parts of India, either all the year round or 

 at certain seasons, and constant vigilance is required to prevent its 

 development and spread on specimens. Large insects when badly 

 attacked may often be cleaned with a smill brush moistened with 

 benzine but small and delicate specimsns, such as Microlepidoptera, 

 are ruined once and for all when badly moulded. As in so mxny other 

 cases, prevention is much better than cure, and every effort should bj 

 made to prevent the entry and growth of mjuld on the specimja^. The 

 best preventive is (1) to see that all new acquisitions are thoroughly 

 dried and free from mould before putting them away in the collection 

 and (2) to keep the atmosphere inside the Store-boxe3, cibinet-drawars 

 or other receptacles thoroughly impregnated with naphthaline vapDur, 

 in which mould is unable to develop from any spores which obtain 

 admittance from the air when the receptacles are opsaal. A plenti- 



