8 BULLETIN lis, UNITED STATES NATIONAL MUSEUM 



The females iu captivity soon lose the quality of shyness, which is so marked 

 during the first day or two afcer emergence, and will then run about uncon- 

 cernedly, even though one is moving objects in the jar, almost as if they had 

 learnt that they were unlikely to be molested. 



Williams (1019) has succeeded in rearing a species of Mulillid 

 from TipMa lucida Ashmead in the Philippine Islands. Since his 

 account adds some details not hitherto described, it is quoted here in 

 full : 



The country about Los Banos abounded in " velvet ants " or Mutillidae — many 

 of small size. As these insects are known to parasitize the cocoons of various 

 solitary bees and wasps, I was able to rear a small, two-spotted species from 

 a bred cocoon of Tiphia lucida. On August 30, 1916, I buried seven cocoons, 

 containing the quiescent pale yellowish Tiphia larva, in soil in a tumbler and 

 introduced a small Mutilla with two white spots on her abdomen. On Sep- 

 tember 3, I cut open these cocoons and found that two of the quiescent Tiphia 

 larvae had been parasitized by Mutilla. In the one case the Tiphia larva had a 

 Mutilla egg transversely arranged on its dorsum between the first and second 

 thoracic segments. The egg was semitranspareut whitish, about five times as 

 long as thick, somewhat curved, rather broadly rounded at one end and conical 

 at the other. Under a hand lens its surface showed numerous pointed granula- 

 tions. The second parasitized Tiphia had an active Mutilla larva a day or 

 two old on the underside of the body. Like the egg, its skin was also finely 

 roughened. It required about four days to become full fed, consuming all its 

 prey. It failed to spin a perfect cocoon, but remained as a quiescent, dull 

 whitish larva for about eight days before changing into a pupa, which a few 

 days later hatched into a female wasp. 



I succeeded in getting several other Mutilla ovipositions. One cocoon con- 

 tained two Mutilla eggs. The cocoon's envelope is not visibly perforated by the 

 ovipositor of the parasite. 



Ferton (1921) has made some observations on Stenorriutilla argen- 

 tata var. saundersivora Ferton, which differ in some respects from 

 those already mentioned. The host of this Mutillid is Osniia 

 sofundersi Vachel. Ferton states that the Mutillid egg in this case is 

 attached to the interior wall of the Osinia cocoon. AVilliams, on the 

 contrary, found the G^g attached to the Tiphia larva, as stated above. 

 Ferton also observed two Mutillid eggs in one Osmia cocoon, but says 

 that one was empty and dry ; he does not describe the exact position 

 of the Mutillid larva on its host, but says that it was toAvard the 

 middle. 



Ashmead and Davidson (1897) write: "The eggs of Sphaeroph- 

 thahna anthophora Ashmead are deposited with that of the parent 

 host before the cell is sealed up, and they probably share with the bee 

 larvae the food stored in the cell, and only attack the bee when it is 

 fully grown and which it is seldom able to completely devour." This 

 seems A'^ery unlikely, since Mutillid larvae are not known to feed on 

 pollen and honey such as is supplied the larvae of Anthophora; and 

 furthermore, in all cases Avhere the life history is known, the adult 

 female Mutillid deposits her eggs through the wall of the cocoon or 

 cell of the host upon the prepupa or pupa of the host. It is further 



