The Marsh Treaders 



glued to the stems of gnisses along the stream. They are about 

 two mm. lonu and are spindle-shaped. The number of eggs 

 must be small, since they are so large that four or five would till 

 the abdomen of a female. They are covered with a horny 

 coating which has longitudinal ribs, and are marked with a 

 hexagonal pattern. In seventeen days the young insect emerges 

 from the egg and molts five times before becoming adult, it 

 feeds upon the juices of insects which fall into the water, and, 

 of course, there are many of these along the grassy borders of 

 ponds. Mr. Martin has seen ten of these little water bugs sur- 

 round a single insect, all of their heads in the direction of common 

 interest, and their bodies radiating outward. The body and legs 

 of the bug are covered with minute hairs which prevents the 

 creature from becoming wet, and it is constantly engaged in 

 lifting its legs into the air and drying them, for if they become 

 wet they sink through the surface film of the water. 



