56 Psyche [April 



Ancistrocerus capra de Saussure, 



The habits of this wasp have been recorded briefly by the 

 Peckhams (1900), who describe three successive nests cons- 

 tructed by this species in the mouthpiece of a tin horn. Their 

 observations differ from mine in that they found the duration of 

 the egg stage to be four days instead of two. These authors point 

 out the similarity of the habits of this species to those of the 

 European A. nidulator de Saussure, observed by Fabre (1891). 

 The Raus (1918) have published observations on a nest made by 

 capra in a woody elder twig, in which the innermost cell was of 

 much greater capacity than the seven (one empty) additional 

 cells, but no mention is made of the sex of the wasps reared from 

 the nest. Observations of Rev. T. W. Fyles, reported by Ash- 

 mead (1894), show that this species provisions its nest with larvsB 

 of the larch saw-fly (Lygceonematus erichsonii Hartg.) Unfor- 

 tunately I did not preserve any of the larvse used by capra, but I 

 am almost certain that in this case they were lepidopterous 

 rather than of saw-flies. It seems probable that species of An- 

 cistrocerus do not limit themselves to a particular kind of cater- 

 pillar, but avail themselves of whatever desirable food may be 

 abundant. 



Nest No. 6. At 3:30 P. M. on June 20, I observed a large 

 Ancistrocerus apparently just selecting her nesting place. She 

 made repeated entrances, coming out each time and flying off for 

 a short distance, apparently carrying nothing. She was possibly 

 making a long distance locality study. Soon she began to bring 

 in mud, out of which she constructed a basal partition at about 

 7 mm. from the interior end of the tube. During the cons- 

 truction of this partition I took many liberties with the nest, 

 removing the glass tube during the wasp's absence and sometimes 

 failing to get it replaced before she returned. She seemed little 

 disturbed. Once, as she hovered before the window sill where 

 her nest should have been I slowly placed it in front of her and 

 she entered as though nothing had happened. Perhaps as a 

 result of this interference, she abandoned her first partition and 

 started another about 5 mm. from the first. When this was 



