THE DEVELOPMENT OP AXTS. 



eggs " erroneously to the cocoons or even to the larva; and pupae of 

 many of our species. In a few groups, like the Attii, the eggs are nearly 

 spherical or broadly elliptical, but in most species they are elongate 

 elliptical (Fig. 45, a). In certain Ponerinse (Parasyscia, Lobopclta, 

 Poncra, etc. ) they are unusually long and slender and may be described 

 as cylindrical ( Figs. 37, a, and 40, a ). The yolk, like that of the bee's 

 and wasp's egg, is very thin and liquid and is enveloped by a delicate, 

 transparent shell, or chorion. As in other elongated insect eggs, the 

 longitudinal axis of the future embryo and adult insect is clearly pre- 

 determined and corresponds with the long axis of the egg. One of its 

 poles therefore foreshadows the anterior, or 

 cephalic, the other the posterior, or caudal end 

 of the ant. There are said to be no differences 

 in the eggs corresponding- to the castes into 

 which they develop, but this matter requires 

 further investigation. It is certain that the 

 eggs deposited by the same female often vary 

 considerably in size and shape, and those laid by 

 the workers are sometimes only half as large as 

 those laid by females of the same species. As 

 the ants frequently lick the eggs it is possible 

 that the saliva may be absorbed by osmosis and 

 increase their volume. This salivary coating is 

 also important in causing' the eggs to cohere in 

 packets so that they can be quickly and easily 

 carried away in case of danger. It is prob- 

 able, moreover, that the saliva contains some 

 antiseptic substance which prevents the de- 

 struction of the eggs by fungi. 



\Yhile the eggs are passing out of the oviducts of the female they 

 may be fertilized with some of the spermatozoa stored in the sperma- 

 theca, or they may pass the orifice of this organ and escape trom the 

 body without fertilization. The latter, is, of course, always the case 

 in old females whose supply of spermatozoa has been exhausted, or 

 in workers, which usually lack the spermatheca and are not known 

 to mate with males. According to a well-known theory, advanced by 

 Dzierzon for the honey-bee, the unfertilized eggs develop' into males, 

 t 1 -e fertilized eggs into females or workers. Although it has beer, 

 shown by a number of authors, and especially by Miss Fickle ( igos/), 

 that unfertilized eggs develop into males, Tanner ( 1892), Reichenbach 

 ( 1902), and Mrs. Comstock (see Wheeler, 19030, pp. 835, 836) have 

 recorded observations which indicate that the unfertilized eggs of 



FIG. 37. Parasyscia 

 aitgitsUc. (Original.) a, 

 Eggs : b. young larva, 

 lateral view. 



