272 



Microscopical Essays. 



furprizing, therefore, that they are found fo numerous in years 

 which are favorable to their propagation. But the Creator of 

 all things has for our fakes limited this abundant multiplication, 

 by raifmg up hofts of enemies, who, befides ficknefs, Sec. deftroy 

 the fuperfluous quantity. 



The following is a calculation of the fecundity of the queen 

 bee, by M. de Reaumur: he found that fhe laid in the two 

 months of March and April 12,000 eggs, fo that the fwarm which 

 left the hive in May confifted of near 12,000 bees, all produced 

 from one mother ; but thefe calculations all fall fhort of thofe 

 which were made by Leeuwenhoek on a fly, whofe larva feeds 

 on flefh, putrid carcafes, Sec. which multiply prodigioufly, and 

 that in a fhort fpace of time. One of thefe laid 144 eggs, from 

 which he got as many flies in the firft month ; fo that fuppofing 

 one-half of thefe to be females, in the third month we fhall have 

 746,456, all produced in three months from one fly. 



Of the Food of Insects. 



Infects feed upon all kinds of vegetable and animal fub fiances ; 

 there is fcarce ,any production of thefe two kingdoms which does 

 not ferve for food to fome kind of infect. They may, therefore, 

 be confidered under two heads, thofe which live on vegetables, 

 and thofe which are fupported by animal food ; each infect knows 

 the food which is proper to fuftain it's life, it knows where to 

 feek it, and how to procure it. It has been already obferved, 

 that feveral infects, when arrived at a ftate of perfection, feed 

 after their transformation upon food totally different from that 

 which nourifhed them in their larva flate ; yet thefe are informed 



by 



