HYMENOPTERA. l r 



(Fig. 20) which in attitude and colour closely approximate to the stems or bark 

 to which they cling. Figs. 25 and 26 show two beetles resembling sheep's droppings. 

 Fig. 17 exhibits one of the May-flies like a dead leaf, and Fig. 21 two plant-bugs 

 which secrete threads of white wax and appear as tufts of woollen matter. 



Characteristics The general characters of the Hymenoptera will be more or less 



of the familiar to most readers from their acquaintance with the well- 



Hymenoptera. ]- nown members of the wasp, bee, and ant tribes. The scientific 

 name by which the order is known is derived from the fact that the upper and 

 under wings on either side are linked to each other by a series of minute hooks on 

 the one which cling to a fold in the membrane of the adjacent margin of the other. 

 The group includes the saw-flies, wood-borers, gall and parasitic wasps, ichneumons, 

 ants, spider-killing wasps, solitary and social wasps, and solitary and social bees. 

 The number of species known is from 30,000 to 40,000, though from our know- 

 ledge of the proportion which they bear to other orders, it is computed that there 

 may be upwards of 150,000 species yet to be discovered. In specialisation of 

 structure they undoubtedly rank amongst the most highly developed of the 

 Insecta. The neat, agile frame, hard shining integuments, stout mandibles, strong, 

 light wings, and movable abdomen, bearing, in the case of the female, at its apex 

 an ovipositor of great power and precision of application, or modified into an instru- 

 ment for sawing and boring in some species, and in several families becoming a sting. 

 All these features combine with a temperament of extreme nervous energj' to give 

 them a character for general intelligence, and a power of adapting means to ends 

 such as are manifested in no other allied order. The web-making spiders alone 

 resemble them in this respect, and we are able to find few analogies nearer than 

 the intelligent action, individual or concerted, of man himself. The social 

 Hymenoptera, such as ants, bees, and wasps have solved, on their own life-plane, 

 industrial difficulties and social problems, pressing for solution in the various 

 societies of men. Doubtless this has been accomplished to a certain extent 

 only at the cost of a loss of individuality such as civilised man would not 

 tolerate for a moment. When we find that the worker-ants, bees, and wasps 

 have, during their specialisation as workers pure and simple, lost their sexual 

 faculties, that the members of a species of Amazon ant during their specialisation 

 as warriors have lost the power of even feeding themselves, being entirely depend- 

 ent on slaves for their food, we may well pause before concluding that such 

 solutions of important problems are in the end for the best, at any rate so far 

 as concerns the human race. 



Without entering into the more minute details of structure, the general 

 characters by which the order maybe distinguished are as follows. The posses- 

 sion of four transparent wings, a head, thorax, and abdomen distinct from each 

 other, the latter joined to the thorax by a narrow stalk, or, in the case of the 

 Tenthredinidce by a broad uniting joint. The integuments are strong, hard, 

 shiny, and often hairy. The mandibles arc well developed for biting purposes, 

 while the subordinate mouth-parts are. in the case of the honey-bees, modified to 

 form a long tongue-like proboscis for extracting nectar from flowers. The head 

 is more or less globular, bearing compound eyes and several ocelli on the crown 

 between and just behind the antennae. The mandibles are used, besides the 



