-58- 



2nd. — One must in his observations take account only of distinctions 

 which are possessed by every species of the same genus and every speci- 

 men of the same species as well as in both sexes if the female is perfectly 

 developed. 



As based upon these laws venation, head and palpal structure, the 

 legs and their armature are none to be reckoned in generic determination. 

 Classification practically rests ist— upon the visible and evident shape of 

 the wings, and 2nd — upon the method of the design of the markings of 

 the wings. For the first account is taken of the various edges, whether 

 rounded, angulale, straight or concave — ^of the various angles, whether 

 sharp or rounded ; for the second account is taken of the number of cross 

 lines upon the fore and hmd wings, and their shaping in lines, bands, 

 points, &c. 



Following this, the author gives his rules cif nomenclature, &c. , 

 tables of the altitude and geographical distribution of species. These are 

 followed by a synopsis of genera and a general description and systematic 

 arrangement of species. The three plates given so far with the work are 

 intended to place before the eye the author's ideas oi influences, cold, 

 heat, elevation, plant life, &c., which in the North temperate Zone have 

 affected and which now to an extent modify its Geonietrid P'auna. 



With regard to the System of the author, after a tletailcd examination 

 we, fail to see how it can be called more natural or less artificial than 

 systems based upon venation or the structure of the various jjarts of the 

 body. We fail to see either right or reason in forbidding for the deter- 

 mination of genera the use of structural distinctions which are ascertained 

 only by use of the microscope. We fail to see anything of exactness 

 gained by using for determination things so variable as wing shape, 

 or so wonderfully changeable as the design of the markings upon the 

 wings. We fail to see that this latter which is unsafe for specific deter- 

 mination, can be used in any way as a basis for generic distinction. The 

 system seems to be the outgrowth of a feeling we have often realized, viz. : 

 that the systems of the past are unsatisfutory, and to an extent artificial. 

 But we would not think it either ralioiial or necessary to cast away all 

 the past has done, because we find its work incomplete or disappointing. 



Some of the innovations of the author we are inclined to endorse. 

 Among the number we note the Latinizing and correct spelling of generic 

 names, as Fuboea for pAibvja, Marmoropteryx for Marmopleryx, Loxo- 

 gramma for Lozogramma, etc. 



The author in his Bibliography m.ikes no reference to the BiiUeliii of 

 llie Brookl. Fnt. Soc, Entomologica .Xincricana, Papilio, the Canadian 

 Entomologist, or anv works i.ssueil b\- our Government, except Dr. 

 Packard's Monoi;ia])li. Dr. Packard's work seems to have l>een the sole 



