FECUNDITY OF INSECTS. 345 



between the muscles, nerves, tegumentary organs, &c., and in the still 

 smaller lacunae that exist between the fibres or constituent lamellae of 

 the various organic tissues. The fluid thus diffused is characterized by 

 the presence of globules or corpuscles of determinate shape ; and in most 

 cases it is easy to ascertain by means of the microscope that the circula- 

 tion is carried on in a system of irregular cavities, much in the same way 

 as the blood of vertebrate animals is in the vascular system with which 

 they are furnished. 



(903.) Innumerable are the means employed by nature to keep the 

 balance between the increase and destruction of the insect tribes ; and 

 countless enemies are provided for the purpose of checking their inordi- 

 nate accumulation. 



Fig. 173. 



The Hive Bee (Apis mellifica). A, Working Bee. B, fertile female, or Queen Bee. 

 C, the male, or Drone. 



(904.) Among the most remarkable provisions for preventing super- 

 abundant fertility is that law which compels the most prolific insects to 

 live in large societies, and permits but one female out of a multitude 

 to lay eggs. As an example of this, we may take the Hive-bees*, so 

 remarkable for their elevated instincts and industrious habits. A 

 swarm of bees consists, first, of females whose sexual organs remain 

 permanently in an undeveloped condition, usually called the workers 

 (fig. 173, A) ; secondly, of perfect males or drones (c) ; and thirdly, of a 

 solitary fertile female, called the queen (B), which gives birth to all the 

 progeny of the hive ; and thus, instead of 20,000 or 30,000 eggs being 

 furnished by every one of as many females, one female only is permitted 

 to be instrumental in perpetuating the species. 



(905.) The Termite Ants likewise, were it not for a similar restric- 

 tion, would soon, by their overwhelming increase, depopulate whole re- 

 gions of the earth, and render the countries in which they are met with 

 absolutely uninhabitable by their extreme voracity. A community of 



* For ample details concerning the habits of these interesting creatures, the reader 

 is referred to Dr. Bevan's work ' On the Honey-bee; its Natural History, Physiology, 

 and Management.' 1 vol. 12mo. London. 



