6 HALF HOURS WITH HfSECTS. [Packard. 



was 32.8 per cent. lu Germany, according to Latreille, 

 the larva of a species of moth (^Psilura vionacha) consumed 

 whole forests." In Eastern Prussia, three years ago, more 

 than 24,000,000 cubic inches of fir had to bo cut down 

 because the trees were attacked by insects. 



In view of these facts let us now look at some points in the 

 life of an insect. Thougli the process of building up the 

 tissues of the body by cell growth had not been distinctly 

 enunciated, Ilcrold had given in the remarkable plates to 

 his " Disquisitiones" clear representations of the gathering 

 of the cells ; and, as the result, the faint line of tissues just 

 entering upon the threshold of life in outlines too vague to 

 admit of a guess as to what the future animal might be. 

 Then the division of the elongated body into distinct rings, 

 and the gradual, though but partial, evolution of organs, when 

 antenna, jaws and legs are all alike to the eye of the beholder, 

 leave it yet a question whether any further development is 

 to be arrested here, and the creature remain the lowest of its 

 type, or still pass on to higher grades, following unerringly 

 the law impressed upon its being. The embryo itself sets 

 the question at rest when it eats its way through its shell, 

 and after devouring its former habitation, as it often does, 

 settles down quickly upon the leaf it is born upon, and 

 forthwith begins its riotous life. 



Before Von Siebold had published his tract upon a parthe- 

 nogenesis* among bees and moths, it was currently believed 

 that the bee grub was developed into a drone, queen or neuter, 

 according to the quality of the food or " bee bread" it was 

 fed with. But this acute and painstaking i)h3'siologist, by 

 the aid of intelligent and scientific bee masters in Germany, 

 brought out these astonishing facts in the generation of in- 

 sects : that the queen bee, after her marriage flight far up in 

 the air, laid two sorts of eggs ; that while some of the eggs 

 were, at the will of the queen, fertilized and produced Avorkers, 



*That is, the production of young from a virgin insect. 



6 



