Americana 



tfOL I. 



BROOKLYN, DECEMBER, 1885. 



NO. 



Aletia xylina vs. A. argillacea* 



By C. V. Riley. 



Without entering into any general discussion, which would be out 

 of place here, as to whether Hiibner's names should be adopted or not— 

 a question which has always divided entomologists — but following those 

 who, taking the more conservative view, accept his species when his de- 

 scriptions and figures leave no question as to what is intended, the 

 purported description in connection with the figures, would have to be 

 rejected even from this standpoint. In point of fact they leave every 

 doubt as to the species intended, and give us no absolute certainty. The 

 only descriptive part is that referring to the white dot, and this is con- 

 spicuously and well represented on the figure referred to; but it is this very 

 character which makes it morally certain that some other species than 

 xyli?ia Say was intended; for while typical specimens of xylina invariably 

 have the three white minute dots referred to on page 9, of this work, the 

 conspicuous discal or reniform spot on primaries is almost invariably* 

 oval and dark, with two cinereous pupils, which are often dilated so as to 

 represent a large cinereous spot, with a dark center and a dark border. 

 Of the many hundreds, and we may say thousands, of specimens which 

 we have examined, not one has had the distinct white spot described and 



* This article is taken from advance sheets from the 4th Rept. U. S. Entomolog- 

 ical Commission and to give point to it I reproduce Hiibner's original description. 



"Aletia Argillacea. Aus Bahia. Vom Herrn Sommer abgelassen. Eine 

 Noctua genuina und Heliophila lineata. Sie ist der A. Vitellina sehr ahnlich, hat 

 aber in nichts eine Gleichheit mit ihr und auf den Schwingen einen weissen Punkt. 

 Ihre Fiirbildung 399, 400, stellt ein mannliches Muster vor." 



This may be translated: "From Bahia. Left by Mr. Sommer. A Noctua genuina 

 and Heliophila lineata. It is very similar to A. Vitellina, but is in nothing identical 

 with it, and has a white dot on the wings.' Figs. 399 and 400 represent the male." 



The question as to what argillacea really is, will be considered in a special study 

 of the genus Anomis which I hope soon to make. From material so far studied it is 

 a species received from Bahia, somewhat smaller than xylina. 



