188 NEBRASKA STATE HORTICULTURAL SOCIETY. 



Not so, however, are the modes of reproduction among insects. The 

 honey bee is produced in three forms, viz., queen, worker, and drone, 

 each with a special duty to perform. The queen is female, the drone 

 male, and the worker usually considered neither or neuter. A worker, 

 nevertheless, often lays eggs which produce drones, while the queen 

 lays them which produce either form, according to the size of cell in 

 which they are deposited or the care of the young after hatched. 

 Ants exist in several forms, males, females, workers (major and minor), 

 and warriors. Some species of insects produce their young alive and 

 are without sex, while in other species there are a number of forms, 

 all of which produce young. 



Most insects are very prolific and produce upwards of a hundred 

 young for each brood ; and but few species occur in which more than 

 a year is required for a generation. By far the greater number of 

 species produce several or many successive broods annually. Professor 

 Riley in one of his reports on injurious insects writes as follows con- 

 cerning the modes of reproduction belonging to the Grape Phylloxera : 

 " The full life history of the species exhibits to us no less than five dif- 

 ferent kinds of eggs. 1. The regularly ovoid egg, 0.25 mm long and half 

 that diameter, of the normal, organic, and apterous female, as it is 

 found upon the roots. 2. The similar but somewhat smaller egg of 

 the gall-inhabiting mother. 3. The female egg from the winged 

 mother, rather more elliptical and 0.4 mm long when matured. 4. The 

 male egg from the same, J less in length and rather stouter. 5. The 

 impregnated egg 0.32 mm long, still more ellipsoidal and with peculiar 

 sculpture and anal point. We have also the peculiar spectacle of an 

 egg from the winged mother increasing from 0.34 mm (its size when laid) 

 to 0.4 mm (its size just before hatching), giving birth to a perfect insect 

 0.4 nim long, and this without any nourishment, laying an egg 0.3 2 mm 

 long. A being thus born, and without food whatsoever, lays an egg 

 very nearly as large as that from which she came." So prolific are 

 some insects that a single aphid (plant louse) is capable of producing, 

 through its frequent generations without pairing, the enormous number 

 of nearly six billions of descendants in a single year. It is by such pro- 

 digious multiplication that the tiny, often despised, insect attains an 

 importance in the economy of nature not even accredited to the raven- 

 ous beast of prey, which is many thousand times larger. 



An insect, because it is such, is not necessarily injurious. Far from 



