MAY 



OVA] 



As the geologist, to be successful at his favourite pursuit, 



" Must dig out buried monsters, and explore 

 The green earth's fruitful crust," 



so the entomologist ought to be willing to devote himself, it may be, to the 

 somewhat "dry " work of studying the earlier stages of the insects he collects, 

 and not allow the more engrossing attractions of merely catching the imagos 

 to solely occupy his attention. This is the more necessary to bear in mind 

 now that the work of the season is beginning to crowd upon the collector. 

 He should not "shut his apprehension up," and drop, it may be, into his 

 old habit of merely amassing numbers of species, without making a corre- 

 sponding addition to his knowledge regarding them. As he pursues his way 



"through matted fern, and hazels thick," 



the eggs of many species may be found by critically examining the food-plant 

 at the time they are due ; but a more certain method of obtaining eggs is 

 to induce the female imago to deposit on a sprig of the food-plant. With 

 this view, all female specimens from which eggs are desired should be 

 isolated, and placed under the most favourable conditions for ovi position. 

 Many species readily deposit theii eggs in a chip, or other box ; others prefer 

 the gauze, or cheese-cloth cover of a breeding-cage, or a spray of the larval 

 food-plant ; some can be induced to lay when placed in a glass tube or a 

 glass shade, with a sprig of the food-plant, or of blooming heather, or a 

 small piece of jam ; and others, especially the butterflies, love the stimulus 

 of air and sunshine. 



One of the difficulties the breeder from the egg encounters is a prompt 

 supply of the proper food-plant. Valuable species are often lost from 

 neglect or mistake on this point. The most successful mode of meeting this 

 difficulty is doubtless by having a growing plant ready, with the eggs placed 

 upon, or near it ; and this must be supplemented by other growing plants as 

 the first- one becomes demolished. Sometimes, however, the greater diffi- 

 culty meets us of not knowing what is the food-plant in a state of nature. 

 Every effort should be made to discover this, as we cannot be said to have 

 worked out the life-history of an insect, though we may succeed in feeding 

 it up from the egg, unless we have ascertained the natural food-plant, and 

 thus accomplished it. Watching the female imago deposit her eggs is one 

 of the surest and most satisfactory methods of solving this problem, and 

 should always be carefully looked for, whenever opportunity offers, in all 

 cases of imperfectly known species. Pieces of the various kinds of herbage 

 among which the species is most frequently found should be in readiness to 

 be first offered to the newly emerged larvae ; and if these are refused, we must 

 then resort to substitute-food-plants. Happily we have many available. 

 For the Geometrina the common knotgrass (Polygonum aviculare) occupies 



