1895.] OVl [Grote. 



have a strictly representative species in occidentalis G. and R., and the 

 same is true of 3. Jochesera, where we h^ve faneralis G. and R. Of 4. 

 Acronicta, we have probably several species, such as lepusculina, vulpina 

 and felina. Of 6. Cuspidia, I know of none, but it is not unlikely that 

 an analogue of megacephala may be found. Of 5. Apatela, it is probable 

 that we have several, but the synonymy is not clear, since Abbot's 

 aceris (acerieola) and hastulifera are not surely made out. Guenee's 

 and Walker's hastulifera is = americana Harris. Of 7. Pharetra, we 

 have impressa Wlk. (oerrillii G. and R.), and probably others. Of 8. 

 Arctomyscis, we have sperata Grt. Of 9. Viminia, I know of none. 



10. Bisulcia ; our superans Guen., must be compared. A comparison of 

 the imago alone has led me to the belief that we are very rich in species 

 of Tritena, such as morula, quadrata. But the great mass of species 

 must yet be compared carefully with the European types and every 

 effort made to keep down the subgeueric synonymy. The following 

 names have it seems, no European representatives : 



11. Megacronycta Grt., 1874, type : americana (this may fall in with 



the subgeneric title Apatela). 



12. Lepitoreuma Grt., 1873, type : ovata ; increta, hamamelis, limsitata. 



13. Mastiphanes Grt., 1883, type: xylinifonnis ; edolata, extricata, 



palUdicoma, Uthospila. 



Lepitoreuma is notable from the shape of primaries and the raised 

 scale. 



I have said that the groups here indicated are of unequal value and a 

 study of the European species had led me to consider the advisability 

 of uniting 7 and 8, as also 1 and 3. To the extraordinary structure of 

 the larva of Jocheajra it would seem in any event right that a separate 

 name should be applied ; the imago is near Triaena, and from the pupa 

 Dr. Chapman places it in the same group. This type brings up the 

 whole question of "representative " species, a subject full of interest. 

 The imagos of the European and American species show recognizable 

 differences, while the extraordinary larval type has maintained itself 

 apparently unchanged. In the Annals of the Lyceum of Natural His- 

 tory, December, 1876, I showed that the differences between such 

 species are shown upon the upper surface of the fore wings chiefly, and 

 of this the species of Jochesera are an example. But Prof. J. B. Smith 

 has shown that between the European Agrotis augur L., and the 

 American Agrotis haruspica Grt., the most important distinction is to be 

 found in the structure of the male genitalia. As I have pointed out, this 

 would prove that the pattern of 'Ornamentation may be more persistent 

 than characters of ultimate sti'ucture ; since, that both these now 

 separable and separated species had a common origin, admits of no rea- 

 sonable doubt. In the Bui. B. 8. N. 8., i, 130, quoted by Prof. Morse 

 in his address before the Section of Biology of the Am. Ass. Adv. Sci., 

 1876, I showed the probability that the larvae of Apatela had varied 



PROC AMER. PHfLOS. SOC. XXXIV. 149. 2 X. PRINTED DEC. 6, 1895. 



