﻿160 Neiv York State College of Forestry 



Moderate cold does not play such an important part as severe and 

 sudden changes in temperature do. This may kill them or slow-up 

 considerably the life processes. 



The nymphs of the first instar are very delicate and readily 

 subject to mechanical injury such as may occur during hard rain- 

 storms, wind-storms and the like. A very small drop of rain will 

 drown a nymph of the first or second instars. 



Secondly, they are enemies of their own kind as was shown in 

 the discussion of habits. This cannibalism extends throughout all 

 stages, seemingly becoming greater as the nabid approaches 

 maturity. There are other predaceous insects which very likely 

 prey upon them — as certain reduviids and phymatids. Spiders 

 and birds, too, are probably formidable enemies. 



A parasite was observed on a nymph when the latter was about 

 ready to moult the second time. It appeared in the form of a very 

 small red sac hanging on the ventral side of the body. It grew 

 larger every day and after the sixth day left the insect. It was 

 probably because of the parasite that the nabid failed to moult, 

 remaining fifteen daj^s in the second instar. The average duration 

 of this stage is about four days. Dr. H. E. Ewing of the Division 

 of Insects, Washington, D. C, kindly identified the parasite as 

 belonging to the family Tromhidiidae, or "Harvest mites". 

 Shannon (1914), in his paper, ''Habits of Some Tachinidae, " 

 states that N. roseipennis is parasitized by Leucostuma atra. 



Nabis rufusculus Reut. 



Since A', roseipe^inis Keut. and N. rufusculus Reut. are so 

 similar in a great many ways, the discussion in the first part of 

 this paper dealing with the economic importance, methods of 

 procedure, etc., for A^. roseip'ennis maj' safely be applied to 

 A", rufusculus. 



Classification and Distribution 



A", rufusculus was first described by Renter in 1872. It belongs 

 to the order Hemiptera, suborder Ileteropicra, family Nohidae 

 Costa and genus Nahis Latriele. 



This species is also practically transcontinental in its range 

 in North America, occuring from British Columbia to New Bruns- 

 wick and Colorado to Virginia. It has been reported from the 

 following regions : Ontario, Maine, Massachusetts, New York, 

 Maryland, New Jersey, New Hampshire, Vermont, Connecticut, 

 District of Columbia, Virginia, North Carolina, Colorado, Northern 

 and Western Canada. 



Genitalia 



The last segment of the male is concave at its dorso-lateral sides, 

 very similar to that of A^. roseipennis. A clasper extends across 

 each one of these concavities (Fig. 33). Unlike the claspers of 

 JV. roseipennis, the anterior ends are much broader (Fig. 34) and 



