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AND 'llf 



JOURNAL, OF VARIATION. 



Vol. XVI. No. 1. January 15th, 1904. 



On a Second Generation of our Forres Triphsena comes, Hb. 

 [melanozonias, Gmel.] . 



(efr. Ent. Record, xv., pp. 217-222.) 

 By LOUIS B. PBOUT, F.E.S. 



"With his usual alertness in seizing opportunities for advancing our • 

 knowledge of the workings of heredity in the lepidoptera, my friend 

 Mr. Bacot tried for and obtained pairings in the brood which I have 

 described in my previous article as brood A. On account of the diffi- 

 culty of making sure of the sexes of the Triphaenas when alive, he 

 placed four specimens in a pot together, which, as the event showed, 

 proved to include at least two females, the others both being prohablt/ 

 males. All four were of the melanic {curtisii) series, but I cannot say 

 what were the precise shades of colour. Two were observed in cop., 

 and from the ? of these — which were of course removed from the 

 pot — ova were obtained, which yielded the brood that I shall describe 

 as brood C. Ova were laid in the pot after this segregation, thus 

 proving the presence of at least one other $ . The parentage of the 

 batches which I shall discuss as D, E, F and G, is not quite so certain, 

 but Mr. Bacot believes it was different from that of C. Of course the 

 grandparentage was identical in all cases. 



The ova were laid in March, and resulted in imagines from June 

 25th to the first week in September, so that we completed our second 

 generation in scarcely over the twelvemonth from the first eggiaying. 

 My notes are based on my own specimens (four only, bred June 25th 

 to July 6th, belonging to brood C, some infectious disease most unfortu- 

 nately carrying off" the rest of my larvte), Mr. Bacot's (73, also brood 

 C, bred throughout July, and stragglers afterwards, the two latest — 

 both very small specimens — not until the first week of September), 

 Mr. J. E. Gardner's (24, bred July 12th to July 28th, from about 24 

 ova, which I call brood D ; Mr. Gardner has no recollection of a single 

 death in the larval or pupal state and there are no cripples), Mr. W. 

 J. Kaye's (five only, brood E), Mr. A. W. Mera's (eleven, brood F, bred 

 in July, a good many dying in pupa), and Mr. V. E. Shaw's (28, brood 

 G, many ova did not hatch). The moths show no sign of degeneracy 

 through inbreeding, being quite fully scaled, and well up to size. Mr. 

 Bacot's extremes measure 43mm, (two dark) to 3imm. (two 

 " typicals "), mine 40mm. (my brightest red) to 37mm. (my blackest), 

 Mr. Gardner's 44mm. (four or five, all of the curtmi — clarki section) 

 to 39mm. (two, one " typical," one citrtisii). The average size of Mr. 



