252 [Aprils 
This solitary egg was found on June 13th. I will give the obser- 
vations made on that day, as they derive a special importance from the 
fact that the two previous days had been so dull that spinipes was not 
at work, nor neglecta moving about. I expected in consequence to 
find cells constructed on days previous to these two dull days contain- 
ing larve of neglecta of some size, and cells constructed and stored 
only that morning; and that in those of the latter that contained 
neglecta, I should find it as an egg. Nor was I disappointed: there 
was the gap in the ages of the larve in the cells of that day and those 
of previous work ; and in one solitary instance, as noted above, I found 
the egg of neglecta. I could find with this egg no trace of the egg of 
O. spinipes, and this makes it just possible that this may have been an 
egg of C. ignita, and that the habit of the latter differs from that of 
CO. neglecta in the parent C. ignita destroying or removing the egg of 
O. spinipes at the time that she lays her own egg ; though my obser- 
vation of the oviposition of C. ignita in 1869 would seem to contradict 
this, and the inference is, that the egg of O. spinipes was lost in opening 
the cell, as already noted. 
It is certainly not the habit of C. neglecta to remove or destroy the 
egg of O. spinipes, but I believe that she injures it, probably with her 
ovipositor at the time of laying her own egg. C. neglecta remains in 
the egg-state but avery brief period; on June 13th, as noted above, 
I found in each of two cells of that day’s construction a newly-hatched 
larva of CO. neglecta, which could not have been lain as an egg more 
than an hour or two, if solong. The following notes of the state of 
the cells containing newly-hatched C. neglecta larvee are my data for 
assuming that the egg of O. spinipes is injured by the oviposition of 
C. neglecta, and that it is not attacked by the larva of O. neglecta. In 
one of those found on June 13th, the CO. neglecta was separated from 
the egg of spinipes by a green grub. The contents of its intestine | 
were dark coloured, being derived from a green grub, not yellowish as 
they would be if from the egg of spinipes ; but the egg of spinipes was 
wrinkled and shrunk to about half its proper size, the amount of 
growth of the neglecta being, however, not nearly so much as the loss _ 
sustained by the egg of spinipes. In the other instance met with on 
June 13th, the egg of spinipes was not detected. On June 15th, | 
I found a cell containing a larva of O. neglecta already sufficiently _ 
grown to be in process of casting its first skin. 
In this cell was the empty egg-shell of spinipes, and the young | 
larva of spinipes dead and shrivelled to about half the size of its 
egg, injured, and glued in drying to a green erub, but apparently not 
