412 " 



thereafter, in the gelatinous matrix around tiie eggs of the mollusc Snccinea 

 retusot Lea. 1 hey did not occur in egg masses recently laid. As the eggs 

 develop, the matrix gradually disintegrates and a large number of minute 

 f!agellat«s develops in the matrix during this process of disintegration. 

 This, ill part, accounts for the presence of the Tardigrada, for they were 

 feeding on the flagellates, the disintegrating matrix or both. 



On May 15, one was taken containing 10 eggs which almost filled the 

 specimen. June 15, one was taken with 11 eggs. Others taken at this time 

 also contained eggs. 



None was taken after June 15. Those taken on this date were captured 

 with a silk net in open water. 



Hexapoda — 

 Notonecta sp. 



This backswimmer emigrated from the pond when it dried up, if it had 

 been present previously. It was not observed during the spring of 1909, 

 but since that time it has been abundant. 

 Limnobates lineata sp. 



Frequent near the margin of the pond. 

 Hygrothechus sp. 



This water strider was first observed March 7, 1909. They appear 

 soon after the ice melts and remain until the freezing weather. Adults 

 hibernate. They are primarily the scavengers of the surface, yet the 

 rapidity with which they perform their work makes observation difficult, 

 as the following example indicates : On Mar. 24, 1910, an ichneumon fly 

 accidentally fell into the water. Instantly it was punctured by three 

 of these water-striders. In spite of its larger size and powerful struggle, 

 the ichneumon was soon reduced to practically an empty shell. 

 Cnemidotus 12-punctatus Say. 



Always present on plant stems and debris. Noted by Blatchley as 

 more conunon in northern part of State than in southern. Hibernates. 



Cnemidotus mutieus Leclerc. 



Occurs with preceding species. Rather more common. Hibernates. 



Hydrocanthns iricolor Say. 



Present in considerable numbers throughout the year. 

 Laccophilus maculosus Say. 



