xvi ANIMAL LIFE 



family The life-history of the common gnat The breath- 

 ing pores of the larva and of the active pupa The emer- 

 gence of the fly The development of the mosquito and its 

 relation to malarial fever The life-history of the harlequin- 

 fly (Chironomus) Its larva the 'bloodworm' Variation 

 in its colour related to the nature of the water The 

 phantom-larva of Corethra The life-history of Midges : the 

 owl-midge (Ccratopogon) The black-fly (Simulium) The 

 adaptations of its larva and pupa to life in running water 

 The drone-fly (Eristalis) Adaptations to larval life in stag- 

 nant water General conclusions on the life-histories of 



Diptera . 240 



The Hymenoptera : 



Efficiency of their care for their young Complexity of 

 their communal life The less highly organised families of 

 this order The saw-flies, gall-flies and ichneumons The 

 nature of galls and their mode of origin The two generations 

 of gall-flies The solitary wasps The key-hole wasp The 

 nest and its stores of food The sand wasp (Ammophila) 

 Mode of construction of its nest Mode of capturing prey 

 and storing the nest The social wasps Their nests and 

 workers Solitary bees Prosopis a primitive type The 

 burrowing and carder bees Cuckoo bees .... 263 



Evolution of the hive-bee The first indications of 

 association in burrowing bees The first attempts at comb- 

 construction The appearance of workers at first casual in 

 Hahftus, becoming a settled habit in bumble-bees The 

 construction and ventilation of bumble nests foreshadowing 

 the perfect comb of the honey bee The importance of good 

 seasons in assisting the evolution of the higher bees 

 Behaviour of Arctic and Mediterranean bumble-bees The 

 tropical Meliponas The high degree of perfection attained 

 in the colonies of the hive-bee 284 



The nests of ants The care of ants for their young The 

 swarming of ants Longevity of ant-queens Foundation 

 of an ant-colony Conditions that produce queens, drones, 

 or workers Aberration of the nursing instinct . . . 294 



