— 15— 



Agroiis stgetum = i,xana Grt. This reference is doubtfully made 

 fide Grote in his list tif 1875. ^i^<^ texana is not known to Mr. Moeschler 

 in nature. I have seen both sexes o^ segeiuju as well as texana and find 

 them totally different. Mr. Giote's reference was probably made on the 

 faith of erroneous information as to the European species. I do not 

 believe that segetum occurs in our fauna. 



There are eleven other species o{ A gratis cited as common to both 

 continents — viz: CharJinyi, baja, spaiosa, C. nigrum, plccta, fennua, 

 ravi, saucid, ypsilon, prasina, and occulla, and as to those I believe him 

 correct, though all the references had been previously made. 



At some future date I shall have some criticisms to make of others 

 of Mr. Moeschler's original references. I would here simply call atten- 

 tion to the fact that all is not done when it has been determined that 

 there are no constant differences in color and maculation between species 

 on both sides of the Atlantic. All those forms which are at home in 

 North America are presumably distinct, and onl}' the most careful com- 

 parisons of structure should determine whether the species are really 

 alike. A certain amount of exception to this applies in the case of the 

 circumpolar tauna, and of species which extend far northwardly. The 

 great similarity of surroundings, and the extreme probability that at 

 some time a connection existed between the circumpolar countries, gives 

 countenance to the idea that the fauna is largely identical, and to this 

 opinion I am led by what I have thus far seen of'that fauna. 



As to Mr. Moeschler's paper as a whole, it bears evidence that the 

 author is a firm believer in the identity of a large percentage of the Lepi- 

 doptera found in Europe and North America, and his comparisons are 

 all made with a view to prove identity. Too much importance is placed 

 on color and maculation, and. not enough on structure. Mr. Moeschler's 

 references, where they are original, must be carefully verified before they 

 are accepted. 



Eyes of Insects. 



In No. 2 of the Journal of the N. Y. Microscopical Society, is an 

 article on "compound eyes and multiple images", interesting as well to 

 the Entomologist as to the Microscopist. There is considerable infor- 

 mation about the general structure, and especially interesting are the 

 notes on the differences of size in the facets of some Tabanidce, and the 

 probable difference of function. Mr. Williston's paper on »S>'/'/)/i/c/<j? shows 

 that this difference in size of facets occurs also in that family, and also 

 that it has some generic value. J. B. S. 



