104 



THE ZOOLOGIST. 



are found in these situations from having been attracted to the 

 reflecting surfaces of sky-lights, for it is well known that water- 

 beetles, with their imperfect sight, mistake large expanses of 

 glass, such as are presented by greenhouses, for sheets of water. 

 Especially attractive, however, to these large water-bugs are 

 electric lights, and notices have appeared in the daily press 

 of the swarming of these, as well as other insects, about the 

 electric lights of cities. In flight, as Mr. Brackett states in the 

 letter from which I have already quoted, the species of Belosto- 

 midse which he observed can rise directly from the surface of 

 the water. 



These insects differ, according to the species, as to their mode 

 of egg-laying. Some, like the common Zaitha fluminea of our 

 northern waters, lay their eggs on their own backs. In my 

 ' collection I have a specimen of this species, which has her back 

 almost entirely covered b,y a nicely-arranged layer of elongated- 

 oval dark-brown eggs, which number over 175. These eggs 

 are set nicely upon one end, and placed in transverse rows, 

 by means of a long protrusile tube, or ovipositor, which the 

 insect can extend far over her own back. This mode of oviposi- 

 tion insures the safety of the eggs until the young are hatched, 

 The eggs are fastened to the back of the naother by a very thin 

 layer of a waterproof gum secreted by the insect. The entire 

 layer of eggs is apt to split from the insects when they are dried, 

 and consequently is rarely seen in collections of insects. The 

 young bug hatches from its egg by means of cutting out a 

 round lid from the top of the egg, and, at about the time when 

 the young brood begins to hatch, the mother sheds the entire 

 layer of eggs fi'om her back, something as she would moult her 

 skin during growth. It is probable that all the species of 

 Zaitha carry their eggs about with them, while, on the other 

 hand, some, if not all, the species of Belostoma deposit their 

 eggs in masses, under boards and logs, near the margins of the 

 pools which they inhabit. 



The young, upon hatching from the eggs, go immediately on 

 their predaceous course, often feeding at first on young snails. 

 As is true of most Hemiptera — the bugs pi'operly speaking — the 

 young differ little from the adults except in the absence of wings 

 in the former. In Belostoma the young, liowever, have two 

 claws on the tarsi of the fore-legs, while as adults tliey have only 



