Insect Ichneumons. 



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of the beneficent activities of these friends 



of theirs than does the average townsman. 



The female ichneumon-wasp lays her 



eggs in or on the bodies of her victims, and 



the grubs that issue from the eggs become 



internal or external parasites. In most 



cases they lack the power of feeding upon 



the structures of their hosts, and can 



only suck up the blood or h'mph that 



circulates about the body cavities. This 



is the reason why the victim does not at 



once succumb, but survives until it is time 



to assume the chrysalis condition, by 



which time its parasite or parasites will be ^''"''"*>'] [H.Mam.F.E.s. 



^ . . ^ Ichneumons Escaping. 



ready to perform a similar change, and TIic numbirs of the gardcu-whitebutteraies are reduced bvtho 



. , ■' . . . action of certain small ichneumon-wasps, which lay theii 



either leave the VlCtmi to transform outside numerous eggs in the body of the caterpillar. By the time the 



, . .... T rr chrysalis should be changing to a butterfly the ichneumon-grubs 



nim or remain m the hOSt-Chr\'Sa!lS. if have finished their work and after passing through their 



. , ... it', , chrysalis stage emerge as winged Insects. Three times the 



the victimized Jnsect could onlv learn .ictuaisize. 



a lesson from human beings as these can from the Insects, it would adopt the very 

 modern defence of the " hunger-strike." 

 If the ichneumoned caterpillar would at 

 once desist from feeding, the parasite 

 would soon die. The caterpillar would 

 die also, but as the attack of the ichneu- 

 mon always results in death this would 

 only be a slight anticipation of a foregone 

 conclusion, yet it would benefit the race. 



It should be stated that there are 

 some real flics — two-winged — that follow 

 a similar mode of life, but at present we 

 are not taking them into consideration. 



One of the most plentiful of the 

 ichni^'umon-wasps is a minute species which 

 might, and ought to be known to every 

 possessor of a garden, for it does great good 

 by its destruction of tlie white bullerflv- 

 caterpillars that raxage tlie cabbage- 

 patch. Clusteis of small \-ellow cocoons 

 containing the chrxsaJids of this species^ 

 may be seen commonly upon fences and 

 palings where the sick butterflv-cater- 



pillars have crawled, rniortunateh', the Pi'otohy] [ii. Mam,F.E.s. 



Ichneumon Chkysalids. 



average person imagines these cocoons to .■Xn idea of the number of ichneumons engaged in the destruction 



1 ,1 /• , 7 J L -TT /i\ 1 1 "f "■"^' caterpillar or chrysalis may be obtained from this 



ne tJie eggs of tllC CaiCyplllar (!) , and as a rule photogi;aph, which shows over sixty chrysalids taken from one 



,1 1 ", 1 1 •,-,,•, 1 chrysalis of the small garden - white' butterfly. Magnified 



ttiev are aestroN'ed ; whereas, il lett alone, three times. 



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1 .Microyastcr elomcratiis. 



