THE ENEiMIES OF BUTTERFLIES. 1611 



lay from two hundred to five liundred eggs, it is plain that tliere must he a 

 vast loss of life. Certainly uinty-nine one-lumdredtlis of every brood 

 perish before maturity, and even after maturity is I'eached a very consider- 

 able proportion of the remainder must come to an untimely end within a 

 day or two of birth. The chief sources of destruction arc bad weather, 

 creatures which seize upon and devour them, and parasitic enemies which 

 place their young within their bodies. 



More must be laid to bad weatlicr than is, I think, generally considered. 

 I have frequently observed that in a heavy storm a very considerable num- 

 ber of new born caterpillars have been washed from their stations to the 

 ground, and doubtless have perished ; and although older caterpillars, chrysa- 

 lids and eggs are rarely if at all injured in this way, I have often noticed 

 the disastrous etiect of a severe rain upon the butterflies themselves. It 

 is especially true when the butterflies are either freshly born or are some- 

 what old and enfeebled. One Saturday just past the middle of June I took 

 careful notes of the butterflies which were abroad, and on the following 

 Wednesday (a two days' rain entervening) took special pains to note the 

 relative numbers of the same species, the two occasions being only three 

 days apart. Xow while on the first day worn specimens of Phyciodes tharos 

 were by no means uncommon, on Wednesday but two were seen, besides 

 one fresh specimen, doubtless emerged since the rain ; Eurymusphilodice, 

 which had not been uncommon, was scarcely seen at all ; Heodes hypo- 

 phlaeas was in a similar case ; Thorybes pylades was not one-fourth so 

 abundant as on the earlier date ; Thymelicus mystic was seen only three 

 or four times to some double that number previously ; and of Limochores 

 taumas only one or two seen where ten or a dozen had been observed on 

 the previous day ; Polites peckius was not one-fourth so abundant as Ijefore ; 

 whUe Ancyloxipha numitor was hardly seen at all on Wednesday, when it 

 had been plenty enough the jjrevious week. The only exception among all 

 the buttei-flies specially noted on the two occasions was with Cissia eurytus, 

 the numbers of which did not seem to be at all affected, and which perhaps 

 owed its exemption to its forest habits, where it would be better protected 

 from a storm. 



Insectivorous animals seem to be especially dangerous foes in earliest life, 

 the eggs and young larvae before they have moulted being subject to many 

 marauders in the shape of ants, spiders and crickets, and doubtless also 

 snails and slugs ; but the caterpillar is subject to attacks from this source 

 throughout its entire though brief life. At this caterpillar stage birds are 

 their principal external foes. Many observers in this country have re- 

 corded the contents of the stomachs of birds ; some of these observations, 

 and especially those of Professor Forbes, have been made and recorded 

 with the greatest care ; but among a considerable number of birds exam- 

 ined by him, not a single one was found to contain the caterpillars of but- 



