166 THE ENTOMOLOGIST. 



The pseudo-chrysalis of Sitaris Colletes exhibits this interior 

 metamorphosis — as seen through the semi-transparent 

 corneous tegument — afler about ten weeks, towards the end 

 of July or the middle of August ; the perfect beetle emerging 

 usually the following month ; although in some rare instances 

 — attributable, as M. Valery Mayet conceives, to insufficient 

 nutriment in the primitive stage, when the Colletes-egg has 

 been partially tapped by other competitors — the ultimate 

 metamorphosis is protracted until the autumn of the following 

 5'ear. In Sitaris humeralis, however, such retardation is the 

 general rule ; it being only in exceptional cases that some of 

 these remain scarcely more than a single month in the 

 pseudo-chrysalis state, completing their metamorphoses in 

 August, and emerging shortly after. But they usually 

 hyhernate in the former stage; and it is only in June of the 

 second year that the interior quasi-larval form is separated 

 from the pseudo-puparium, and about five weeks later 

 becomes transformed to a true pupa-nympli ; the same 

 month, in fact, when the adult larva had assumed its 

 corneous tegument in the previous year (Fabre, I. c, pp. 

 339 — 343). M. Valery Mayet recognises this pupa as " /« 

 veriiahle nymphe'''' (p. 75); therefore the antecedent stage, or 

 " troisieme larve'''' of Fabre, and not his ''^ pseado-chrysalide,^'' 

 can alone constitute the pseudo-pupa ov ''^ psettdo-nymphey 

 Thus the Sitaris humeralis usually requires two years to 

 complete its metamorphoses, hybernating the first year in the 

 primitive larval condition, and the second in that of the 

 pseudo-chrysalis ; whereas the Sitaris Colletes, commencing 

 its operations seven months earlier, generally attains maturity 

 within a single year. The early transformations of two other 

 species of Melo'idas have also been investigated by M. Jules 

 Lichtenstein, of Montpellier, who succeeded in nurturing one 

 of the primitive larvae of Meloe cicatricosus on the egg of a 

 Vespa vulgaris placed upon honey in a glass tube, and in 

 witnessing its first metamorphosis five days later, when it 

 plunged into the honey, but died after feeding thereon twelve 

 days. This secondary form differed essentially from that of 

 Meloe, described and figured by Fabre, apparently constituting 

 an intermediate stage, closely resembling the antecedent 

 larva, but destitute of caudal setae, with lacteous head and 

 black eyes (the subsequent stage being blind), looking like a 



