September iSysJ 



psrcHE. 



281 



HVDROBATIDAE. 



62, llydrotrcchus remigus Say. 

 Frequent. Hibernates beneath logs 

 and piles of drift along the border of 

 streams. Sometimes seen warm days 

 in latter part of February on the 

 surface of the water. 



63, Li»niotreclnis niarginatiis Say. 

 Frequent. All that I have found in 

 winter were beneath logs on hillsides, 

 200 yards or more from water. 



64, Limnoporus rtifoscutellatiis 

 Lat. This species, abundant on the 

 lakes of northern Indiana, has l.icen 



found only in small numbers on a 

 large pond in Vigo Co. Two living 

 specimens were found beneath a pile 

 of drift near the border of the pond 

 on Jan. I, 1893. 



The species of Zaitha, Belostoma, 

 Ranatra, and, perhaps, Notonecta, 

 presumably pass the winter as nymphs, 

 inhabiting the mud in the bottoms of 

 ])onds and streams ; but as I have 

 taken none of them at that season they 

 are not incorporated with the above 

 list of winter Heteroptera, which 

 includes only such species as 1 have 

 actuallv found hibernatinsj. 



SOME HABITS OF FORMICA OBSCURIPES FOREL, 

 WITH NOTES OX SOME INSECTS FOUND ASSOCIATED WITH IT. 



BY GEORGE B. KING, LAWRENCE, MAS.S. 



It is generally believed and is also 

 stated by the majority of writers upon 

 the habits of ants, that in such climates 

 as we have in oiu' northern States and 

 Canada, the ants just before the ground 

 begins to freeze go down into their bur- 

 rows below the freezing point, and re- 

 main there until the approach of spring, 

 when they ascend again, attend to their 

 accustomed avocations, and repair their 

 nests. 



To satisfy myself as to whether or 

 not this were true, I last year located 

 and marked three of the mounds in 

 which this ant lives ; they were several 

 miles apart. On November 25 at 3 

 p. M. I went with my son to nest no. i. 

 The temperature of the air was 38°, the 



snow which had fallen on the morning 

 previous had nearly disappeared, and 

 it was gradually growing colder. We 

 removed some of the earth from the top 

 of the nest, and at the depth of six 

 inches we found plenty of ants. They 

 were in a sluggish condition and appar- 

 ently asleep and when disturbed could 

 barelv move about. We continued 

 digging down to the depth of two and 

 one-half feet and found ants huddled 

 together in little piles all through the 

 nest. I took the temperature at this 

 depth, 33° F. The ground froze the 

 following night and remained frozen all 

 winter. We collected 177 of the ants, 

 and brought them home to look for 

 winter parasites on ants. I found 8 



