96 Orthorrhapha brachycera. 



A. cephus F. and fur O. S. were bred from the nest of a mud-wasp 

 in Texas ^ These are, I think, the chief references about the larval 

 habits of Argi/ranioeba; sometimes the pupæ have been recorded as 

 found under stones, they have then evidently come from bee-nests. 

 The young Argyramoeha larva seems to get into the bee-cell at a time 

 when the bee-larva is fullgrown ; it then eats this out in a relatively 

 short time, so that only the empty skin is left, but the bee-larva seems 

 to be ahve during the whole or ahnost the whole time; Fabre declares 

 that this is possible because the bee-larva is in the lethargic stage 

 just before the pupation and its whole inner body is to some degree 

 dissolved on account of the transformation, and I think this may be 

 correct. When the larva has eaten the bee-larva it is fullgrown, and 

 it hibernates in this stage, the transformation to pupa and the devel- 

 opment of the imago following the next summer. — Verhoeff (1. c.) 

 on the other hånd declares that he found the young larva of A. an- 

 thrax in the cell of Hoplomerus spinipes sucking at a Lepidopterous 

 larva stored by the wasp; the egg of the wasp was destroyed, and 

 he thinks this had been done by the Argyramoeba larva; he found 

 the larva on ^^/e at a size of 2 — 2,5 mm. and it pupated on *'/7 ; in 

 this case the larva would seem to feed upon the food stored by the 

 wasp and to pass through its whole development in the spring and 

 summer, and consequently the eg^ or the young larva must hibernate 

 (see below under Bomhylius). With regard to Verhoetf's observations 

 I must however remark that they probably to some degree need 

 confirmation ; the faet that A. anthrax has been bred from the nests 

 of burrowing bees besides from those of fossorial wasps seems to 

 indicate beyond doubt, that it is a true parasite and feeds on the 

 larva of the host; (such is also the case with the larvæ of Chrysis 

 ignita about which Verhoeff states that it is a Guckoo). The pupa 

 works its way out through the often very hard and strong wall of 

 the bee-cell, forming a. cylindrical hole orcanal; for this work it uses 

 the spines on the head, bul that it is able to do so hard a work is 

 astonishing. When the pupa has reached out to the surface, the escape 

 of the imago foUows, the pupa skin being left sticking in the hole. 



The eggs are certainly deposited on the ground or on other 

 piaces near the nests of the bees; Fabre (1. c. 197 and 201) observed 

 A. anthrax [sinimta) and trifasckita approaching the ground when 

 flying and touching it with the end of the abdomen, certainly depositing 

 the eggs; the young, somewhat agile larva has then to penetrate into 



^ Osten Sacken thought the wasp to be a Velopaeus but Riley (Arner. Nat. XV, 

 1881, 443) states that it is a Trypoxylon. 



