58 



Bulletin 64. 



TIME OF FLIGHT OF SPKCIES OF CRAMBUS AT 



ITHACA, N. Y. 



Cr ambus 



laqueatellus Clem... 



leachellus Zinck 



luteal ell us Clem 



jloridus Zell 



giradellus Clem 



albellus Clem 



interniineUus Walk 



mutabilis Clem 



topiarius Zell 



alboclavellus Zell.... 

 caliginosellus Clem. 



elegans Clem 



ruricolellus Zell 



vulgivagellus Cleni. 



Each * represents approximately two weeks. 



SYNOPTICAL TABLE. 

 A. Species that are grayish or dark colored. The free portion 

 of the valve at least five times as long as broad. {The Caligin- 

 osellus Division.^ 

 B. Clasps nearly equal. 



C. No accessory spine ; clasps not anchylosed at the base. 



PI. v., Fig. 2. caliginosellus. 



CC. An accessory spine ; clasps anchylosed at base. PI. V., 



Fig. 3. interminellus . 



BB. Clasps unequal. 



C. Harpe broadened. PI. V., Fig. 4. hulstelliis. 



CC. Harpe reduced to a stout spine. PL V., Fig. 5. 



mutabilis. 

 AA. Species that are yellowish or some shade of red. In the 

 more specialized forms (in all described here except C. luteo- 

 lellus) the free portion of the valve is less than five times as long 

 as broad. (77^^ Luteolellus Division. ~) 



B. Generalized representatives of the luteolellus division. The 

 clasps are nearly equal and are at least five times as long as 

 broad. PI. V., Fig. i. luteolellus. 



