318 
Psyche 
[Vol. 94 
The largest recorded nest of X. nitidulum contained 25 cells 
(Dutt, 1912). Two inhabited nests collected in Janla (Nl, N2) con- 
tained 14 and 2 cells, respectively. Cells are 17.0-22.0 mm long and 
12.0 mm wide at the center, with the mouth 5. 0-7.0 mm in diameter. 
The cells are arranged in a cluster, with the foundations of the first 
three or four cells usually attached to the underside of a horizontal 
surface, such as the ceiling of a man-made structure. The first cells 
are inclined with their axes at about 80° from the attachment sur- 
face, and additional cells are aligned parallel to them, but with their 
foundations displaced slightly so as to be free of the substrate. All of 
the cell entrances face in the same direction; they open upward when 
the nests are attached to a wall. 
The two inhabited nests were located on the ceiling of a dark 
room. Abandoned nests were found in similar sheltered situations, 
e.g., in the rooms and stairways of an abandoned house in the same 
village. The species had evidently been common in ancient aban- 
doned Jain caves at Udayagiri, near Bhubaneshwar, but the walls 
and ceilings of the caves had recently been cleaned, leaving only 
gummy outlines of where the bases of cells had been attached. While 
searching the caves for nests, I noted several black female wasps the 
size of X. nitidulum sitting inside mud and gum-lined holes in the 
cave walls, facing outward as does this species in the cells of the nest 
(see below). Several such holes were sealed with mud and a gummy 
substance. This species thus may sometimes inhabit pre-existing 
holes; but I was unable to collect specimens of the hole-occupying 
wasps for certain identification. 
When collected on 24 November nest Nl contained 1 1 closed cells 
(sealed with mud overlain with gum) and three open cells. One open 
cell was empty, and a day later I found the two other open cells 
contained a single lepidopterous larva, 7.5 mm long, without an egg; 
and a mature wasp larva in the process of spinning a cocoon within 
the cell. N2 consisted-of two cells, one of them empty but lined with 
a silky material as if it had already produced an adult, and the other 
incomplete (in the process of construction). These two nests were 
only about two feet from each other in the same room. I kept nest 
Nl in a jar to see what would emerge from the eleven sealed cells. 
They produced four female and three male X. nitidulum adults, and 
three males of the cleptoparasitic wasp Stilbum cyanurum splendi- 
dum (Chrysididae). The three parasites, and one male and one 
female X. nitidulum emerged before 26 December. The remaining 
