i8 93 . THE HABITS OF ANTS, WASPS, AND BEES. 271 



grouping of the cells, and an association between the mother and 

 her offspring in the perfect state (not simply as larvae) ; the last 

 condition will be brought about by the emergence of the older insects 

 of the brood while the mother is still occupied with the younger 

 larvae or their cells. In a single species of solitary bee (Halictus 

 quadristrigatus) these conditions are almost fulfilled, but the earliest 

 young insects to appear are males, and when the females are 

 developed the mother dies. For the formation of a community, of 

 course, the mother must co-operate with her female offspring, 

 and this Halictus, therefore, just fails to develop the social habit. 

 It gives, however, a sufficiently strong clue to the origin of that 

 habit. 



The difference in habit between bees and wasps gives rise to 

 another interesting suggestion by Herr Verhoeff. The bees, being 

 vegetable-feeders, are more disposed to live peaceably in communities 

 than the wasps. But there is no contact between the mother and 

 larva ; a supply of honey and pollen is placed in the cell, the egg 

 laid, and the cell closed up. The wasps, on the other hand, are 

 mostly insect-feeders, and might be expected, therefore, to be of too 

 warlike a disposition to form well-ordered republics. But their mode 

 of life is such as to develop family affection ; the mother, after laying 

 the egg, goes in search of prey, and from the fossorial habit of placing 

 alongside the egg a paralysed insect to serve as food for the larva, 

 and then closing the cell, has arisen the custom of feeding the larva 

 throughout the preparatory stage, and only closing the cell during the 

 pupal period. 



The nests and habits of many species are described by Herr 

 Verhoeff in detail. Some notes on the wintering of Hymenoptera 

 are of special interest. The winter is passed by various species in 

 all stages, except the egg and the feeding-larva. Curiously enough, 

 insects of the social species are generally found singly in the winter, 

 while individuals of the solitary species gather together in the cold 

 season, as do also some ichneumon flies. A number of males and 

 iemales of a species of Ceratina were found in a bramble stem which 

 they had hollowed out to serve as winter quarters. A winter colony 

 of females of Halictus movio (the males of this species die in autumn) 

 was found in a forked tunnel opening under a large stone. In was in 

 early spring that these insects were observed, and, while a number of 

 the bees were gathered together at the end of one branch of their 

 burrow, others were apparently making their way out of the winter 

 retreat. 



The habits of some bees (Trigcna) at Trinidad have been lately 

 described by Mr. Hart (9). These insects have no sting, and conse- 

 quently adopt special means for defending their nest. The only 

 entrance is by means of a tube which is constricted at intervals 

 so that only one bee can pass. Each of these constrictions would 

 serve as a fortification where a foe might be held at bay. Moreover, 



