332 PHYLUM ARTHROPODA. 



glands. Each egg is enclosed in an oval shell, in which 

 there are several little holes (micropyles), through one of 

 which a spermatozoon enters. Spermatozoa, from the store 

 within the spermatheca, are included in the egg-capsule. 



At an early stage in development some cells associated with the 

 mesoderm are set apart as reproductive cells, and originally these have 

 a segmental arrangement as in Annelids ; at a later stage other meso- 

 derm cells join these, some forming ova, others epithelial cells around 

 the latter. The distinction between truly reproductive cells and 

 associated epithelial cells, which is said to be late of appearing in some 

 of the higher insects, is established at a very early stage in the 

 cockroach, 



Second Type of Insects. The BRITISH HIVE-BEE 

 (Apis mellifica) 



This is a much more highly specialised type than the 

 cockroach. It belongs to the order Hymenoptera. 



Habits. The Hive-Bee (Apis mellifica) is a native of 

 this country, and is the species most commonly found 

 domesticated. It is the only British representative of the 

 genus ApiS) and exhibits, in its most fully developed form, 

 the social life which is foreshadowed among the Humble- 

 Bees. As a consequence of this social life, there is much 

 division of labour, which expresses itself alike in habit and 

 in structure. The males (drones) take no part in the work 

 of the colony, and are wholly reproductive ; the females 

 include the queen-bees and the workers. In the workers, 

 which perform all the work of the hive, the reproductive 

 organs are normally abortive and functionless. In the 

 queens, of which there is but one adult to each hive, the 

 enormous development of the reproductive organs seems to 

 act as a check upon the brain and other organs, which 

 are less developed than in the workers. The workers are 

 further divisible into nurses, which are young and do not 

 leave the hive, being occupied with the care of the lame, 

 and the older foraging bees, which gather food for the whole 

 colony. 



In considering the relation between the life of the Hive 

 Bee and that of many allied forms (Bombus, etc.), it is 

 important to notice that the habit of laying up stores of 

 food material for the winter enables the colony, and not 



