292 BRITISH LEPIDOPTERA. 



S 



177) and a description of some of the hybrids by Miss Morton (Proc. 

 Ent. Soc. Lo?id., 1895, PP- xxxiv — xxxv). The pairings obtained 

 were Platysa?nia cecropia $ X gloveri $ (in 189 1 ), P. Columbia 

 $ X cecropia % (in 1893), P. cecropia $ X calif or nica (ceanothi)* 

 $ (in 1893), Actias lima $ x selene ? (in 1892). Of these only 

 short comparative notes, however, were published, and no detailed 

 descriptions of the imagines or larvae. Among the details noted are : 



I. Platysamia hybr. grifjithsi\ y Tutt [cecropia x gloveri). — The Hybrids are 

 slightly paler than P. cecropia, and the white bar between the ocelli and the margin is 

 with only the faintest trace of the red outer edge so noticeable in P. cecropia. These 

 bars, in the latter, are indented and curved, but in the hybrids are much less 

 indented, and those on the primaries are not nearly so bent as in P. cecropia, and on 

 both wings are broader than in the latter ; outer margin of secondaries of same shade 

 as primaries, not darker as in P. cecropia, the whole insect being slightly below the size 

 of P. cecropia (Watson, Ent., xxvi., pp. 176—177). Miss Morton adds: "The 

 hybrid larvae take equally after both parents — the large size of that of P. cecropia, the 

 bird's-egg blue of that of P. gloveri intensified with lemon-yellow tubercles, most 

 beautiful objects. The largest of the cecropia x gloveri larva? are larger than those 

 of any cecropia I ever saw." 



2. Platysamia hybr. watsoni, Tutt [cecropia x call fomica [ceanothi)). — Nearerto/ 5 . 

 cecropia than P. ceanothi in size and shape of wings, though intermediate in markings, 

 but of a lighter colour than either parent. The costa of primaries of P. ceanothi is 

 straight for three-fourths of its distance from the base, in the hybrids it is arched all 

 the way as in P. cecropia ; the outer margin of the secondaries of P. ceanothi is not 

 rounded as we find in P. cecropia, and in this again the hybrids distinctly take after P. 

 cecropia. The costa of secondaries of P. ceanothihas a dip in them, in P. cecropia the costa 

 is arched ; the costa of the hybrids, as in their primaries, is arched also. The white 

 baron the wings of the hybrids, however, conforms much more nearly to P. ceanothi, and 

 the ocelli of both primaries and secondaries are intermediate in shape between those of 

 their parents, having thewidth of that of /\ cecropiaznd the length of that of P. ceanothi, 

 in which species, as in the hybrids, the outer point merges into the white bar on the 

 secondaries. The underside of secondaries of P. cecropia has a whitish baud, commenc- 

 ing at the base, where it is slightly wider, running round the costa and meeting the 

 white band of the outer margin. In P. cea?iothi this band is nearly obsolete, but on the 

 costa and a little from the base is a pinkish spot. In the hybrids this spot is dilated 

 into an elliptic or spindle-shaped spot, running to the base of the wing on the one 

 side, and on the other side narrowed out into a mere streak along the costa till it 

 meets the marginal band of white, into which it merges (Watson, Ent., xxvi., p. 

 177). Miss Morton notes: "The hybrid larva is not nearly so handsome as 

 that of P. hybr. cecropia x gloveri, and was readily distinguishable from the larva of 

 P. cecropia; the laivas grew to an immense size, though none attained the size of 

 a few ? larvae of the P. hybr. cecropia x gloveri." 



The imagines of both the above hybrids differ so greatly from 

 either of the parents, that they have the facies in each case of a 

 quite distinct species ; but the most remarkable thing about them 

 (and the other hybrids here mentioned) is their total barrenness. I 

 have never known a hybrid to lay an egg, nor the $ to fertilise, 

 though both sexes pair freely with each other and with P. cecropia 

 (Morton). This experience differs from that of Heyer (posted, p. 

 293), and that of Standfuss (posted, p. 300). 



3. Platysamia hybr. americana, Tutt (Columbia x cecropia). — This hybrid 

 varies more than any other here noted, some examples being deep red-grey, others 

 pinkish-grey, and yet others have the ordinary grey colour of P. cecropia (Watson). 



4. Actias hybr. mortoni, Tutt (lunax selene J. — The moths are intermediate be- 

 tween their respective parents, in colour, shape, and markings, though there is a varia- 

 tion towards either of their parents. The hybrids do not show (in those examined) 



* Grote himself [Can. Ent., xxvii., p. 267) calls this rubra. Bohr. (1855)— <7j//- 

 fornica, Grt. {iS6^)z=zceanothi, Behr. (1868). 



f Griffiths notes {in litt.) : "One prominent distinction of this hybrid is the 

 brilliant whiteness of the indented marginal line of the (brewings — the number anil 

 shape of the indentations being as in cecropia." 



