ECONOMY OF HIVE BEE. 21 



by-and-by convert it. No more food is supplied, 

 and the period for cocoon spinning approaches. The 

 silken threads forming this (co, Fig. 4) are produced 

 by a fluid yielded by a gland (Fig. 15), which 

 re-appears in the adult bee. This fluid escapes by 

 an aperture in the lip, and very quickly hardens 

 into what may be described as bee silk. Before the 

 cocoon can be built, a cover, technically called 

 sealing, is put over the larva by its nurses, that 

 now bid it farewell. These covers are seen in num- 

 bers at G, Fig. 3 ; they are pervious to the air, are 

 made of pollen and wax, and are more convex and 

 regular in form than those sealing in the honey 

 (I, Fig. 3) ; and, behind them, a series of most 

 wonderful and bewildering changes occur ; but, ere 

 they can commence, a preliminary step is necessary, 

 which seems to have altogether escaped the attention 

 of both scientific and practical writers. The food 

 given to the larva, especially during the latter part 

 of the growing period, contains much pollen, the cases 

 of the grains of which consist of a substance called 

 cellulose, which is perfectly incapable of digestion. 

 These cases, with other refuse matters, collect in 

 quantity within the bowel, which becomes distended, 

 since it has no opening (mb, Fig. 13). The im- 

 prisoned larva, having little more than enough room for 

 turning, must be freed of these objectionable residua; 

 but Nature is equal to the difficulty, accomplishing 

 all in a manner commanding our admiration — -and here 

 we can but outline, reserving a fuller explanation till 

 we consider the structure of comb. In a word, the 

 larva turns its head upon its stomach, and pushes 



