162 [July. 



emergence) ; B larvje died of mould, and no cocoon contained 

 Chalcids. Of thirty-two examples observed, 11 emerged between 10 

 a.m. — 1 p.m., 13 between 1 p.m. — 10 p.m., and 8 between 10 p.m. — 10 

 a.m. ; I am, however, of opinion that the majority emerge during the 

 night. 



Ichneumons effect their escape from their own or their hosts' 

 cocoon by biting a circular incision around one end, much as a cater- 

 pillar consumes a leaf, saturating it the while with oral fluid — 

 perhaps potassium hydroxide — and, when a sufficient distance is 

 traversed, the operculum is forced outwards (one example emerged 

 through both its own cocoon and a piece of paper gummed over it) ; 

 this is the only usage to which their mandibles appear to be applied, 

 since they subsequently feed only upon juices. In emerging, both 

 Exetastes and Mesochorus rush straight out of the former's cocoon at 

 a great pace, with wings already quite fully developed and usually 

 capable of instant flight, though often damp and sometimes dabbled 

 with pupal liquid. Unlike the Lepidoptera,l\ie?.Q \n^ect& do not quit 

 the cocoon as soon as the pupal state is terminated, but several days 

 are subsequently spent within the former, during which the ultimate 

 state of perfection is attained. I have only once seen Exetasfes in 

 coitu ; Ichneumonidse in general are very rarely surprised in this 

 condition : Gravenhorst, who captured 100,000 specimens during 

 thirty years, met with not one instance of it. In the present case, 

 the pair remained quite quiescent for half an hour ; the ^ held the 

 $ wnth its anterior legs, the hind pair being retracted and in no way 

 in use ; the ^ antennae were porrected, but those of the $ were laid 

 back along the sides of the thorax. 



I have a goodly number of the emerged Exetastes, and shall be 

 glad to give them to any one interested in the subject ; among them 

 the variation is surprisingly small. In both sexes the 2nd, 3rd and 

 4th hind tarsal joints are normally white, rarely flavous after death, 

 and occasionally with the base of the 5th also flavous ; the extent of 

 sessility of the areolet varies somewhat and it is sometimes subpetio- 

 late ; the nervelet is also of variable length, often obsolete. The waZe 

 has the scutellum usually flavous at its ai)ex, sometimes the apical 

 half or the whole scutellum except its base is flavous, at others it is 

 subobsoletely binotated with flavous at its extreme apex or entirely 

 black ; the antennae, which normally bear no pale band, occasionally 

 exhibit more or less distinct traces of one and very rarely the band is 

 quite evident ; the mesothorax is laterally flavous in typical exam])les, 

 but sometimes more or less castaneous, reduced to mere dots or rarely 



