220 ENTOMOLOGICAL NEWS. [May, '08 



shelter of the dense red cedar and juniper growth as far as 

 that went, and then crossed to the lee shore, and dropping 

 down to near the water's edge, proceeded along in the cover 

 of the sand dune until the first breath of the wind was en- 

 countered when they gradually rose in the air and started over 

 the lake on the usual course. The exactitude with which 

 they followed each other was remarkable. One could stand 

 between two red cedars where they crossed to the shore and 

 ninety per cent, of all butterflies would pass within striking 

 distance of a net. Sometimes a lull would come in their pro- 

 cession and the last would be out of sight in the distance 

 before the next appeared but when it came it would appear 

 beating over the same clump of juniper and within a few 

 yards of the exact spot in which the previous ones first 

 hove into sight. 



Whether these were all migrating in the true sense of the 

 word or not I leave to the entomologists to decide. I can just 

 record the facts as I saw them in the hopes that they may be 

 of some interest to others of more experience in the ways of 

 the Lepidoptera. One more fact may be worthy of mention. 

 All specimens of plexippus seen were in good shape, with un- 

 worn wings while most of cresphontes and troilus were more 

 or less worn, especially the latter, few of which had not lost 

 part or all of their tails and were otherwise damaged though 

 not enough to seriously impair their flight. 



Some Larrid Wasps from Colorado. 



BY S. A. ROHWER, Boulder, Colo. 



I wish to express my thanks to Prof. T. D. A. Cockerell, 

 for going over my manuscript. 



The types of the species here described are in my own col- 

 lection. 



Tachysphex nigrescens n. sp. 



9. Length 6 mm. Anterior margin of clypeus rounded out, with- 

 out distinct lateral teeth, shining, sparsely covered with punctures; 

 front dullish, densely and rather coarsely punctured; vertex shining, 

 the punctures not as dense as those on the front; space between the 



