476 



Marvels of Insect Life. 



]\Iost of the family ^ to which the book-louse belongs are small out-door Insects 

 which, if seen at all by others than entomologists, are confused with the plant-louse, 

 which they superficially resemble in size and general appearance. Most of these 

 have w'ings, and there is, therefore, a slight metamorphosis in their development ; 

 but the Insects are active throughout life. They hve upon dry refuse matter, 

 both animal and vegetable, and various small forms of fungi found on decaying 

 wood, bark, etc. The family is a small one, but we have about thirt}^ representatives 

 in this country, though none except the book-louse can boast of an English name. 

 A number of species have been found preserved in amber. The females of this out- 

 door group deposit their eggs in clusters of about ten on the under sides of leaves 

 and, strange to say, cover them with a slight web. How this web is contrived by 

 the winged Insect is not clear. It \\'ill be seen in our photograph on page 478, and 

 it will be found, no doubt, to have some protective value. 



Mason- Bees. 



The natural order of Insects- to which the bees belong 

 stands pre-eminent for the cleverness displayed by great num- 

 . bers of its members as workers in wax, wood, clay, paper, etc. 



jaf In another article we have referred to the wasps who design 



pots and vases of artistic forms, and to the mud-dauber wasps 

 that conceal their cells under massive knobs of mud of their 

 own accumulation. The work of the mason-bee ^ is much akin 

 ^m^-vmtm^ to that of the mud-dauber, except that the bee uses grains of 

 Ji^^ifc '" ^ sand instead of mud, and fits and cements these together with 



^ her own saliva-cement. These Insects occur in the South of 



Europe, and Reaumur told their story many years ago. More 

 recently, Fabre has paid much attention to them, making 

 experiments that help to an understanding of the order of in- 

 telligence displayed. Reaumur told how the mason-bee, 

 having decided upon the site of her nursery, carefully selects 

 sand, grain by grain, for her building materials. These she 

 glues together by means of a viscid secretion from her mouth, 

 until they form masses the size of small shot, and transports 

 them in her jaws to the building site. With a number of these, 

 cemented by the same means, she constructs her foundations. Upon the latter 

 she runs up the walls of a thimble-shaped cell, an inch long and half an inch in 

 breadth. I-Jefore it is roofed in she becomes a gatherer of pollen and honey, with 

 which she stocks the cell, and lays an egg in with it. On her return from one of 

 these collecting journeys, she puts her head into the cell and discharges her gathering 

 of honey. The pollen has been collected on the hairs of her lower surface, and 

 to discharge this she gets into Die cell backwards antl cleans off the pollen in such 

 manner that it falls to the bottom. When the recpiisite (puintity of each of the two 

 ingredients has been stored, she gets her head well into the cell and with her jaws 

 works up the honey and pollen into a homogeneous paste ; then lays her egg and 

 seals up the top of the cell. The construction of a single cell takes the labour of two 



'■ I'socidaj. - llymcnoplera. •' ("iKiliroddini niiiiari.i 



Photo by] [W. West. 



The Book-Louse. 



A minute Insect — here shown on 

 a scale of twenty-five times llic 

 actual size — that may frequently 

 be found among old books, old 

 papers, and neglected stores of 

 various kinds, upon which it feeds. 

 Its destructive powers are chiefly 

 noticeable when it obtains entry 

 to the store-boxes of the ento- 

 mologist. In spite of its mislead- 

 ing name, it is not a parasite. 



