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escapes at the junction of the metathorax and abdomen, either 

 below or above, the seg-ments of the leaf-hopper being ruptured 

 at that point. (PI. VII, fig. 2). In the case of a P. xanthocncmis, 

 however, the larva escaped from the Libitniia by a roundish hole 

 in the mid-dorsal line, at about the middle of the length of the 

 abdomen. This hole of exit is irregular, and has the appear- 

 ance of having been gnawed, but I did not notice whether the 

 larva that emerged was different from the usual type. 



After escaping from its host, the larva as a rule buries itself 

 'beneath the soil, or beneath rubbish that lies on the surface; but 

 in some species it pupates on the leaves of the tree or bush, on 

 which the leaf-hopper was feeding, as in a case mentioned be- 

 low, and in another recorded by Ott, who bred a Ptpimciihts 

 from a puparium found on Ribcs. 



One peculiar feature in some species of Pif>iiiiciiliis is the fact 

 that the surface of the abdomen often bears a number of depres- 

 sions, frecjuentlv variable and of irregular form. Some species, 

 such as P. bciicficiciis, appear to always have these on one or 

 more of the segments and they are not due to post-mortem 

 changes, as one might suppose without the examination of 

 freshl}' caught specimens, but occur in every individual, at least 

 of the male sex, though so variable in number and form. In- 

 deed as a general rule they appear to be more commonly found, 

 or are more developed, in the males than the females, and some- 

 times may even be said to produce a distortion of the body. 

 Whether it is to some such examples that Verrall refers, when 

 he says that he suspects the flies are themselves subject to para- 

 sites I do not know, but it is certain that the irregularities of 

 surface mentioned above are not due to this cause, since they 

 are found in every example of some common species, though 

 only occasionally in others. Pipunculiis, however, is subject to 

 the attack of a Chalcidid parasite of the family Encyrtidae, of 

 which I bred a species from the puparium of P. ciiicrasccns, 

 but whether the subterranean species are likewise attacked it 

 may be very hard to prove, unless the parasite stings the larva 

 of the Pipiinciilus, while still within the leaf-hopper. "This I sus- 

 pect is not the case, or we should probably have bred some of 

 the Chalcids from the numerous species of Pipunculiis that we 

 reared from the larvae. The puparium of P. cincrascens being 

 freely exposed on the surface of the leaves, would naturally be 

 liable to be attacked, and is probably stung at that time. At 

 least it is noteworthy that the one species with exposed pupa- 



