144 NATURAL ARRANGEMENT OF INSECTS. 



honey-dew but where there are Aphides: such, how- 

 ever, often pass unnoticed, being hid on the under side 

 of the leaf. We have some grounds for beheving," 

 Mr. Curtis adds, " that a saccharine substance, similar 

 to that of the Aphis, drops from the Coccus also. 



(134.) The astonishing fecundity of these insects 

 has no parallel in the animal creation. In summer, the 

 young are produced alive from the body of the parent ; 

 but in autumn, the female deposits eggs on the stems 

 of plants, near the embryo shoots, and these are hatched 

 by the sun early in the spring. How beautiful is this 

 care of the Creator for the meanest of his creatures ! If 

 the last autumnal brood of the Aphides was brought 

 forth as the former, the frosts of winter would inevitably 

 kill all, and exterminate the race ; while the same sun 

 which brings the eggs to maturity in spring, expands 

 the young leaves upon which the parent insect intended 

 her future progeny should feed : thus both leaves and 

 insects come into life at the same time. But the most 

 wonderful part of their history is the power of con- 

 tinued impregnation through a great many descents. A 

 pregnant female, kept by itself, produces perfectly 

 formed young ones, which, though kept separate, will, 

 in a short time, produce others ; and thus several gene- 

 rations follow each other. The male insects only 

 appear in autumn ; and this may explain why the last 

 autumnal brood is enclosed in eggs. Reaumur com- 

 putes that each Aphis may produce about 90 young ; 

 and that, in consequence, in five generations, the de- 

 scendants from a single insect would amount to the 

 astonishing number of 5,904,900,000. Were it not 

 that these immense multitudes are called into being to 

 furnish food for other races, they would be sufficient to 

 destroy vegetation, and annihilate the empire of Flora. 

 We accordingly find that, in " due season," they become 

 the prey of many other animals, both in the bird 

 and insect world. During most years, observes Mr. 

 Curtis, the natural enemies of the Aphides are suf- 

 ficient to keep them in check, and to prevent them from 



