REHN AND HEBARD 61 



certainly great individual variation in certain structural and 

 several color features. 



We have examined eleven specimens of the original Cape Cod 

 series on which Scudder based concinnum. Ten of these are now 

 in the Museum of Comparative Zoology and one, a male, is in 

 the United States National Museum. Of the former lot we select 

 as lectotype a male labelled: "0. concinnum, Cape Cod," with an 

 additional round red paper label. The single type of 0. longipen- 

 nis, a female, is in the Museum of Comparative Zoology labelled: 

 "Texas. A. Agassiz. 0. longipennis Scudd.," with an addi- 

 tional red type label. 



The type and paratypes of Orchelimum gracile Bruner (Orcheli- 

 mum delicatum Bruner) are now before us and the only tangible 

 character to separate them from pale faced eastern specimens of 

 concinnum is the longer, straighter ovipositor, which is discussed 

 beyond. Redtenbacher's inerme was proposed merely to replace 

 longipennis, which name was preoccupied in the genus Xiphidium 

 in which he placed it. The description of inerme, when exam- 

 ined, is also seen to be based on the same condition of this species 

 as that to which Scudder gave the name longipeniiis. Blatchley's 

 indianense is absolutely inseparable from dark faced concinnum, 

 while campestre is the pale faced condition of this species, para- 

 types of both forms, now before us, demonstrating this very 

 clearly. 



Taking up the features of variation in this species, we find they 

 can readily be classified under three headings, i. e., geographic 

 and individual size variation, ovipositor variation and general 

 color and structure variation. 



Individual size variation at any one locality is less pronounced 

 in this species than in most of the other forms of the genus, but 

 the geographic size variation is very great. Material from New 

 England is minimum in size, southward along the east coast the 

 bulk increasing until individuals from the southeastern states are 

 very decidedly larger than those from New Hampshire. Speci- 

 mens from Indiana and Iowa are larger than New England indi- 

 viduals but not greatly so, while in eastern Nebraska and eastern 

 Kansas the size is in general as great as in representatives from 

 the coast of Georgia; southward in Texas and northern New Mex- 

 ico the bulk regularly increases, until on the central Gulf coast of 



TRANS. AM. ENT. SOC, XLI. 



