NYMPHALINAE: EUYANESSA ANTIOPA. 403 



in its appearance, being vastly commoner in some years than in others. 

 This has often been noted on both sides of the Atlantic. In 188<), for 

 instance, it was much commoner in New England than in 1885, both 

 around Boston, as observed l)y several, and in places as distant as Hallo- 

 well, Maine (Miss Wadsworth) and 8tow, Vermont (Miss Soule). Mrs. 

 Heustis observed its rarity in New Brunswick in 1878 (Can. ent., xi : 

 39). In England, Mr. Swinton has endeavored to connect its periodicity 

 with the eleven-year cycle of sun spots, by tabulating the number of recorded 

 captures for forty-four years in four columns of eleven years each, the 

 table showing the following numbers of captures of antiojja in each series 

 of four years, commencing with 1832, 1843, 1854, and 1865 : 13, 1, 5, 

 79, 14, 3, 1, 7, 0, 5, 0, — but with indifferent success, as the maximum 

 sun-spot period falls just between the maximum and minimum period of 

 abundance, and the three years of minimum sun-spots show an aggregate of 

 nineteen captures against an aggregate of eighteen for the three years of 

 maximum sun-spots, a difference which is not worth discussing (Nature, 

 XXV : 584 ) . Certainly the first requisite of such an hypothesis should be 

 the common superabundance of antiopa in given years on hoth continents, 

 which no one has yet attempted to show. 



Food plants. The caterpillars live principally upon willows (Salix), 

 and will apparently eat any of the numerous species ; poplars (Populus) 

 of which they seem to have little choice, though they perhaps prefer the 

 Balm of Gilead and Lombardy poplars ; elms, particularly the American 

 elm (Ulmus americana) and Celtis occidentalis, on which Mr. Beuten- 

 miiller has taken it. In Labrador, Moschler says they feed upon Betula 

 humilis, but I have seen no other specification of birch as a food plant in 

 this country, though it is always given as one of the resorts of the larva in 

 Europe. Lang also gives nettle and Kaltenbach linden (Tilia) in 

 Europe ; I should think these errors, but that Mr. H. Edwards informs me 

 that he has taken them on rose bushes in California, the leaves of which 

 they stripped bare after the way they treat willows ; so that some latitude 

 of choice must be allowed them. Doubleday has stated that their favorite 

 food plant in Europe is the willow and in America the elm, but the willow 

 is generally looked upon here as equally the favorite, though the devasta- 

 tion of the elms on cultivated grounds may be a little more conspicuous. 

 Al^bot figures it upon Salix nigra. 



Oviposition. One cluster of fourteen eggs, found by Mr. Trouvelot, 

 was laid July 16 at 2 p.m. ; the eggs were crowded rather irregularly and 

 closely together (one lying on its side), and enclosed half the terminal 

 shoot of a willow at the base of a leaf, most of them occurring upon the 

 under surface of the shoot. Another, a much larger cluster (64:33), 

 almost encircled a twig of elm, two millimetres in diameter, only the upper 

 surface being free from eggs ; they were disposed regularly, bearing a 



