INTRODUCTION. XIX 



stages of the North American NOCTUJE are so incompletely known, that 

 we may expect interesting additions to this class of species. A case, 

 conversely, of resemblance between the larvge and difference in the 

 moths, is offered in this same group, viz: that of the European 

 Jochecera alni and the American J. funeralis. 



The mass of representative species are separable on more obvious, 

 though it may be still slight characters. Among such may be enumer- 

 ated the European Habrosyne derasa and the American H. scripta. A 

 third representative species of Habrosyne occurs in Japan. The Eastern 

 American Thyatira pudens with its aberration anticostiensis, is less clearly 

 a representative form ; the differences, while the general pattern of 

 ornamentation is retained, being somewhat great, while the Western 

 American T. lorata departs still more, and shows a distinct approach 

 to the species of Bombycia. The European Diphthera orion and the 

 American D. fallax, show considerable resemblance, while Acronicta 

 leporina and A. vulpina, may be held to represent each other. There 

 are, however, a number of forms in America, belonging to Acronycta 

 Ochs., which are as yet incompletely known. The North American 

 Agrotis normaniana resembles the European triangulum ; the American 

 A. obeliscoides, the European A. obelisca ; while the American A. clan- 

 destina is separable from the European A. ravida, mainly by the peculiar 

 structure of the female abdomen. There are not only here represent- 

 ative species as between Eastern North America and Europe, but also 

 as between Eastern and Western North America, where, west of the 

 Eocky Mountains, the Californian A. havilce represents A. clandestina 

 of the Atlantic district. The European Cabbage Owlet, Copimamestra 

 brassicce, is represented in America by C. occidentis. In the Mamestra 

 are a number of American species representing, through various grades 

 of resemblance, European forms. We may here compare together 

 nimbosa with the European nebulosa, purpurissata with tincta, atlantica 

 with dissimilis ; while the American Dianthcecia bella and glaciata, much 

 resemble the European magnolii. 



The Russian Oncocnemis confusa is represented in California by 

 0. behrensi, while the genus in America grows to an extent hardly 

 foreshadowed by the few European species. The genus Hadena shows 

 a number of representative species, and perhaps some identical species, 

 not yet sufficiently worked out ; among the latter, H. lateritia will 

 probably be found. The European Hyppa rectilinea is represented in 

 America by H. xylinoides, Actinotia polyodon and A. ramosula resemble 

 each other, and Trachea atriplicis seems to be represented in America 

 by T. delicata. Brotolomia meticulosa is represented in America by B. 

 iris, while the European and American species of Trigonophora 

 (Habryntis) differ strongly in colour. Certain European and American 

 species retaining more or less a superficial resemblance, are found to 

 differ structurally and therefore generically. As such may be cited 

 Cirrnoedia xerampelina and Eucirrosdia pampina. Instances of curious 

 resemblances under this head remain to be noted (consult G-rote, 'Revised 

 Check List,' 43). The European Pyrophila pyramidea is represented in 

 America by P. pyramidoides, thus we have a representative and iden- 

 tical species of the same genus, tragopoginis being found in both the 

 Old and New World. In the genus Litkopliane (Xylina), L. lambda is 

 represented by the American L. thaxteri, while Scopelosoma sateliitia 

 finds counterparts in America among no less than three species, sidus, 



