1907] 
SWETT — GEOMETHIl) XOTES 
121 
GEO:\IETmi) NOTES.— OX MESOLELTA CAESI.VTA, 
HY L. W. SWKl'T, M.\U)K.\, M.VSS. 
As I looked throiiijli the Packard collection at ('amhridge, Ma.s.s., 1 noticed 
that his eastern types of Mcxoleuca cacsiaki Denis & Schill'enniiller were not like 
the Iyuroj)ean ones of his own or iny collection. Mcxoleuca cacxiata in Packard’s 
European collection numbered .some 12 or 15 examples from Staudinger and others, 
the localities beint; I^ajdand, Iceland, Switzerland and Austrian Alps. Ills American 
examples were from Okak and Caribou Islands, also Alt. Washington, Aug. 1-11, 
and specimens from Ilandolph, Vt., in the Boston Society of Natural History. In 
the Proc. Host. Soe. Nat. Hist., Vol. XI, LS66, page 51, he de.scribed V.idaria uurata 
from Okak, Caribou Islands and Alt. AVashington, N. II. He sj)eaks of these as 
haying gohlen scales on the fore wings and on examining the types 1 found they 
agreed with the original de.scriptions but not with the Euro])ean forms. 'I'hus 1 sa%y 
we had two distinct sj)ecies of which 1 note the following. 
In caexiaia European, the hind wings are whitish with traces of brown markings, 
the fringe of both wings being black and white. In some the markings are sharp 
and well defined, being powdered with golden scales. Thedi.scal sj)ot is ])lain and 
distinct, there being a white and black cast to all wings. In cacsiata, American form, 
or aurata, the .specimens are of a brownish cast, smoky as it were and not black and 
white like the Euroj)ean. The hind wings lack the pallid \yhite of true cacxiata and 
are suffused with brown, and there are two white wayy zig-zag lines with brown 
margins to wings. The (fiscal sjiot is suffusc'd and the center of the mesial land is 
not clear, like European, but smoky and diyided though not gray as .some Iceland 
examples or reddish brown as my Piuro])ean examples from Pitcarj)el. Mexoleuca 
flavicincta of Pfurope is a closely allied form to aurata but is so distinct as not to allow 
discussion. The yaricty Mexoleuca inventaria of Grote (Bull. Geol. Sure. 'Perr. 
Hayden VI, .591, 1882), may be a synonym of this but as I haye not seen the type 
I can not say. While working oyer this matter last February, I wrote to Dr. Taylor 
in regard to the western forms, as they were unknown to me; and hea.ssures me that 
they are the same as Eastern, though I belieye he did not haye the dc.scrij)tion as he 
did not then possess a co])V of the description in the Boston .Society Pajx'rs, for which 
he wrote afterwards. No doubt we shall haye an interesting paj)er from him on the 
western form. 
