NATURAL SCIENCES OF PHILADELPHIA. 219 



and tapering. The apex of the wing is touched with fuscous, and the ends of 

 the nervules slightly dotted with the same hue. Hind wings concolorous, 

 pure white. 



Lake Teedyuscong. July. 



Before concluding this paper, I desire to record my views respecting the 

 unnecessary amount of labor, loss of time and uninviting study, which the 

 details of M. Guenee's mode of systemization imposes on the American stu- 

 dent. MM. Boisduval and Guenee, in the important and comprehensive works 

 which engage their labors at the present time, are not writing treatises on 

 local faunae, but on that of the entire world, in so far at least as lepidopterous 

 insects are known ; and students everywhere have a right to expect that 

 the difficulties of classification will be diminished, rather than complicated, 

 by their treatment of the various groups which may be included in their 

 works. The author who would be cosmopolitan in his representation of this 

 subject, at the present day, cannot neglect, in justice to those who may fol- 

 low his footsteps through nature, to endeavor to lighten their burden of study 

 and to economize their time, by leading them with all the lights of his know- 

 ledge, through the complicated mazes of doubt, engendered by the numerous 

 and perplexing affinities existing in beings of the animated world. The chief 

 object of classification is simply to communicate our own systematic concep- 

 tions to others, and to mark the graduations in the arrangement in such a 

 manner, as will enable them easily and quickly to recognize its groups. How 

 has M. Guenee facilitated the recognition of genera, whilst he has greatly in- 

 creased the number of them, or lightened in any respect the systematic labor 

 of the foreign student ? Is it enough that he should content himself with 

 carefully written diagnoses, and compel the student to examine critically 

 and minutely every one in any of his family groups, before being able to 

 decide whether the insect he may wish to classify belongs to any of them, or 

 is not edited ? A system which both reason and convenience approves, is 

 that which enables the student easily to find what he seeks, and not that 

 which compels him to master the genera peculiar to every other portion of 

 the globe, in order to assure himself whether a group has been established 

 into which his specimens can be admitted. 



The omission of synopses of genera, when the number of them in his family 

 groups calls for such tables, as it does so frequently, is a most serious, not to 

 say unpardonable, defect in the six volumes published by M. Guenpe. There 

 is no student of American lepidopterology, compelled to study his works, who 

 will not regret that he has so extensively described our fauna ; and the fact 

 that so much time and patience and labor are necessary to determine whether 

 a generic description is given by the author, of one of our moths, of which 

 everything is unknown, perhaps, except the division to which it belongs in his 

 system, is an actual and real impediment to the development of the study in 

 our country. In the examination and comparison of lepidopterous insects, 

 M. Guenee recognizes beyond doubt, each genus under a family by some dis- 

 tinctive structural trait, and why cannot all these be presented to the student 

 in synopses, as well as they are apparent to his own perceptive faculties ? 

 Without these conveniences of comparative study, the student is compelled 

 to do the work of the author anew, and, at an immense disadvantage and loss 

 of time, to search for what is distinctive, in by no means sharply, though dif- 

 fusely characterized groups, which include very frequently ornamentation 

 as one of their chief characteristics. In the cabinet of specimens, all this is 

 almost apparent at a glance, and it is the result of this educated sense that 

 seizes quickly what is distinctive in a variety of forms, that the student has a 

 right to look for in synopses. 



M. Guenee expressly declares in one of his early works in the "Suites a 

 Buffon," that in giving the meagre synopses of tribes and families, contained in 

 the series, he is merely following the custom of M. Boisduval, and that lie 



I860.] 



