278 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



lific, and which are called Cyclops on account of the single eye in the mid 

 die of the flat head. Owing to its small size the Cyclops proves a wel 

 come food to all young fish. We got»them from a stone basin, about a 

 meter deep, located under large chestnut trees, where the water changed 

 but little and where there were not too many algae. 



In order to obtain a larger number of Cyclops I had a large barrel 

 filled with water from this basin. In doing this I was guided by a rec 

 ollection from my boyhood's days — how that in a barrel containing 

 rain-water numerous exceedingly lively animalcules were observed by 

 us, and it seemed a perfect miracle to our childish thought that these 

 little beings could have originated in the rain-water barrel. I lived iu 

 hopes that the same phenomenon would repeat itself in the present case. 

 The experiment was entirely successful, for in even larger number than 

 the Cyclops there soon appeared new auimalcules, which turned out to 

 be the larva and chrysalis forms of the Culex. How often has the ques- 

 tion been asked, For what purpose is the Culex iu this world, and of 

 what possible use can it be ? [The Culex is simply a musquito or gnat.] 

 Before attempting to answer this question we must notice the life of 

 these insects, and especially of that variety which, on account of the 

 singing noise it makes, is called Culex pipiens, and whose "better half" — 

 only the female Culex stings — causes men on fine summer evenings to 

 express a doubt as to their right of existence. 



If in winter, by means of a candle, we examine somewhat closely the 

 vaulted ceilings and walls of a cellar, we frequently find in moist or dark 

 places hundreds and even thousands of gnats (Culex); these are the 

 females of the generation produced in autumn, which in these sheltered 

 places, in a sort of torpor, wait for spring. When the sun rises higher 

 iu the heavens and warm spring days come, when the ice disappears 

 from pouds and puddles, the gnats leave their winter quarters and be 

 gin the propagating process. For this purpose they seek some sheet of 

 water, settle aloug its edges or on a floating leaf or blade of grass, bend 

 the point of the back part of their body toward the water, and lay 

 their dark-colored long eggs, running to a point. These eggs adhere to 

 each other with their long sides, and when thus united resemble a small 

 boat pointed in front and back and slightly hollowed out on the top. 

 Such a pile of eggs floating along the surface of the water and" adher- 

 ing to the edges is the result of a single act of laying, and contains 

 from 200 to 350 eggs. After a few days the hardly risible larvae slip 

 from the eggs on the side turned toward the water, and move about in 

 this their proper element. The entire process resembles the more easily 

 observed laying of eggs by butterflies, and the hatching of their larvie, 

 the voracious caterpillars. 



The young larvae of the Culex, after they have readied the water, grow 

 rapidly, feeding on exceedingly fine vegetable formations such as are 

 always found in great abundance in the mud of stagnant water, and 

 change their skin several times. They are generally seen floating on 



