POUSTES ATEERIMA. 583 



suspend her architectural labours and to divide her time be- 

 tween the erection of fresh cells and the feeding of the larvae 

 in those which were first made. Soon, however, her labours 

 become more onerous and more complicated. The larvre or 

 grubs, which inhabited the first two or three cells, have grown so 

 rapidly that they are fast becoming too large for their pendent 

 cradles. The cells must therefore be enlarged to suit the in- 

 creased dimensions of the inhabitants. This also is done, each 

 addition being marked by the ridge which has been already 

 mentioned. 



Thus, then, the hard-worked mother insect is forced to engage 

 in three distinct labours, namely, the building of new cells, the 

 enlargement of existing cells, and the nurture of the larvse. A 

 short reference to the illustration will now give the reader a 

 clear idea of the cell-group. Above is a series of completed 

 cells, each occupied by a full-grown larva, one of which is being 

 fed by the mother insect, and below is a series of incomplete 

 cells, each of which has received an egg, but neither of which is 

 fit to sustain the weight of the larvae. If, however, the nest had 

 been allowed to remain in the forest, instead of being carried off 

 to the British Museum, the five lower cells would have been 

 completed like their more perfect predecessors above. 



The observant reader wiU probably have noticed that from the 

 mouths of several cells a scoop-like projection is seen to issue. 

 These projections have been faithfully rendered by the draughts- 

 man, although they denote a certain imperfection in the speci- 

 men. They are evidently the result of hard usage, and show 

 that part of a completed ceU has been broken away. As is often 

 the case, the fracture has its value, inasmuch as it shows that the 

 normal form of the cell is hexagonal, and that the angles are 

 quite sharp and firm without needing either pressure or excava- 

 tion to make them so. 



It is much to be regretted that in England there is no repre- 

 sentative of this interesting group of insects by which the 

 above-mentioned problem might be solved. We might then 

 know whether males and females belong to the same brood, are 

 nurtured in the same cells, and are of the same size. We might 

 learn whether or not the males are bred in separate establish- 

 ments divided from the other sex like dioecious plants. As it is, 

 however, we are in ignorance respecting these points, and no 



