REHN AXD HEBARD 65 



This type is that of portions of Virginia; Maryland and Penn- 

 sylvania individuals are also referaVjle to it. However, certain 

 specimens in both of the larger Virginia series in one or more of 

 these features show the form similar to the type found at the other 

 extreme of the specific range. The species moniicola, the rela- 

 tionship of which to davisi we have already discussed, is in some 

 respects more nearly related to the more northern type than to 

 the more southern type of the davisi complex, so it would appear 

 that the lower land type (f. e. the southern type of davisi) is 

 probably the most recent development and the more northern 

 form the more primitive. On account of the possession of a 

 distinctly curved ovipositor and a characteristically formed 

 subgenital plate in the female sex we would consider 7nonticola 

 the more specialized of the forms. 



Aside from the features above treated we find that specimens 

 of davisi from the higher elevations represented in Pennsylvania 

 (Broad Top Mountain and Diamond Valley) and Virginia (Stony 

 Man Mountain) show a reduction in size when compared with 

 material from lower elevations. Material from the extreme 

 borders of the range is little different in the proportions measured, 

 aside from an increase in the length of the pronotum, caudal 

 femora and of the ovipositor in material from Indiana and Iowa. 



The ovipositor form variation, which has been treated under 

 Morphological Notes, shows a geographic correlation; the females 

 from Pennsylvania northward and from Ohio and Indiana have 

 an ovipositor with a straight or very faintly convex ventral 

 margin and an apex which is not truly ventral in position, while 

 those specimens from Maryland south to Virginia have, as a 

 rule, ah ovipositor with the ventral margin straight or very 

 faintly concave and the apex distinctly ventral. In the ArUng- 

 ton and Orange series, however, we find both types present. 



Biological Notes. — From the available information it is seen 

 that this species appears adult during the latter half of June and 

 early July, and is present in that condition to at least the first 

 week of September. The earliest date for mature specimens 

 is June 16, at Great Falls, Virginia, and the latest September 7, at 

 Diamond Valley, Pennsylvania. Immature individuals repre- 

 senting three instars were taken on June 4 at McConnellsburg, 

 Pennsylvania, and others belonging to the same instars on June 



TRANS. AM. ENT. SOC, XLII. 

 3 



