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A;Lirr<)tls hariiHpica Grotn. 



Tlie foi-c til)i;ie are spiiiosc This species is puVjliblied by Dr. 

 Spoyer iis A. <t injur \iiv. (jniui/is', in an cvlremely valuable papr-r in 

 uliicli the rcliitioii.ship botwcfn allied iMinis of Noctiiidae in .NOrth 

 America and Europe are discussed. All such closely allied lurins 

 must have descended from some common progenitor, and I iiavo 

 suggested that the se])arati<)n may have occurred in later Tertiary 

 times, and is the ett'ect of the change in tenipiratnre (luring the 

 Glacial Period. The effect of a gradual increase in cold would have 

 been to drive the menil)ers of the Artogaeal fauna southward and 

 separate geograpliically the Euro])eanand American species. There 

 appear, as previously noticed by Dr. Le Conte in the Coleoptera, to 

 be various grades of relationship between species now existing in 

 Europe and America. AVhile some are absolutely identical, others 

 may be distinguished by various grades of distinctional character, 

 grades that could only have been brought about by gradual changes, 

 and yet which, in the Noctuidae, as Dr. Speyer interestingly shows, 

 have some common direction of variation in color that is apparently 

 the result of climatic conditions. The specific name quite evidently 

 loses some of its hitherto accepted force as applied to these forms. 

 Nevertheless, where we can constantly separate the forms, different 

 names should be employed for the sake of exactness of definition. 

 The present name was published January 20tli, 1875, and Avas pro- 

 posed to replace that of unimacula, given to the species by Mr. Mor- 

 rison, a name previously nsed by Dr. Staudinger for an Andalusian 

 species. 



Agrotis exsertistigma Morrison. 



I have previously considered this specific name to apply to 

 aUernata Grote. At that time I was guided by Mr. Morrison's 

 brief comparative description and my California material of ciipid- 

 issinia Grote. I have now returned to me my specimen by Mr. 

 Morrison, and I find it to be distinct from either aJternata or 

 ciipida, with neither of which should it have been compared by its 

 describer, for the abdomen is not flattened, but conical. It must 

 therefore be referred to a different subsection of the o-enus. I 



