264 



Marvels of Insect Life. 



Photos by] 



The Ichneumon of the Large White Butterfly. 



[H. Main. F.E.S. 



One of the ichneumons that keep the large white butterfly in check is the pimpla, here shown in three of its stages. First, a chrysahs 

 cut open to show the ichneumon-grub after eating up the contents. The second photograph shows similar chrysalids containing 

 chrysalids of the ichneumon ; and the third photograph is of the female ichneuinou arrived at full development. 



if he detached the mouth of the parasite it could not again seize its victim and 

 continue the sucking process. The caterpillar manages to construct its cocoon, 

 and then the ichneumon-grub emerges and spins its own cocoon within the other. 



In some of these ichneumons we find an extraordinary development of the 

 egg-placer — so extreme in certain species that if we did not know the facts from 

 those who have observed the Insects at large, we should imagine that Nature had 

 overshot the mark and made these organs so large as to be ineffective. There 

 is the rhyssa,^ for example, that lays its eggs in the grub of the horn-tail sawfly, 

 which feeds in the solid wood of pine-trees. The egg-placer is as fine as a hair and 

 of great length ; yet it is said to be thrust through the bark and wood exactly 

 above the spot where its victim is feeding out of sight. How so fine an instrument 

 can be manipulated so as to pierce thick wood is a marvel. An American species, - 

 shown in one of our photographs, has the hind-body in the female drawn out to an 

 inordinate length to serve, no doubt, for probing deep and narrow burrows, such 

 as those in the earth where lie the eggs of locusts, and the crevices of bark. It has 

 been stated by Doubleday that they pierce wood with this hind-body, and he declares 

 that he found twenty or thirty of them that had perished through inability to 

 withdraw their bodies from wood they had pierced. The male, it should be stated, 

 has a hind-body of quite normal proportions. 



The Brimstone- Butterfly. 



It is a noteworthy coincidtiiCL' that the abundant flower that is generally 

 accepted as typical of spring-time, and the earliest butterfly of the year should 

 be of the same uncommon tint. It is a great pity that the fathers of Iiritish 

 entomology, who gave most of the popular names to our butterflies, should have 

 missed the opportunity they had of calling the butterfly by the name of the flower 



^ Rhyssa persuasoria. 



- Pclcciniis polyturalor. 



