144 Messrs. Prout and Bacot. On Cross-breeding of [Jan. 8, 



intermediate, and a few rather dark. F 7 (ex light $ x dark ? ) consists of 

 32 specimens, extremely uniform, all intermediates, with fairly distinct dot- 

 lines. F 8 , 44 specimens, again vary, yet with no absolutely pure white, and 

 only 3 or 4 very strongly dark-dusted, nothing extraordinarily dark. Duplicate 

 pairings were here obtained ; from a rather dark <J x rather light ? , sprang, 

 as F 9 (labelled fix ©), 28 specimens having a similar range to F 8 ; from an 

 apparently intermediate pair, the ? darkened in outer margin, 33 specimens, 

 rather constant, intermediate, nearly all well dusted on a whitish ground. 

 Fio, 2 specimens only, agree with the F 9 brood last mentioned, from which 

 they sprang. 



Brood G. — This cross was obtained, but not propagated beyond the single 

 generation (F 6 ). The brood consisted of 69 specimens, slightly more variable 

 than most first crosses, yet in no way startling. Most are quite normal 

 intermediates, 2 or 3 might better be classed as dark, yet not extreme, 



Brood g. — Continued to generation F 10 . In F«, 35 specimens, the variation 

 is inconsiderable, all being intermediate, though such variation as there is is 

 towards the " light " side. F 7 was obtained from a lightish pair, and yielded 

 4 lightish specimens. F 8 , 47 specimens, was again rather constant, a light- 

 intermediate. F 9 was obtained in duplicate ; one batch (labelled g ix Q, 

 parents rather weakly marked) consisting of 18 specimens, intermediate, 

 nearly all weakly marked, the colour ranging from darkish to lightish without 

 extremes ; the other batch (g ix from a better-marked pair) considerably 

 variable, 49 specimens, mainly well-lined, about 12 almost the pure Hyeres 

 form, 3 or 4 approaching the London form, many intermediate. Fi , 

 47 specimens from the last-named brood, follows it well on the whole, nearly 

 all being well-lined, though there is much variation in tone and many 

 (especially of the darker ones) are rather strongly darkened towards the outer 

 margin. 



Brood H. — Continued to the second generation of the cross, that is, to F 8 . 

 F 7 , 56 specimens, is very constant, and very typical of the normal " first 

 cross " — all intermediate. F 8 , 49 specimens, is very variable ; hardly any are 

 quite pure light, only 1 or 2 pure dark (and not very intense) ; but there is 

 almost every other variation, in size, strength of markings, general facies, 

 and ground-colour. 



Brood h. — Continued to generation Fi . In F 7 , 12 specimens, the variation 

 is very slight, all being lightish intermediate. F 8 , 36 specimens, is decidedly 

 variable, the range being from pure light to darkish intermediate, with the 

 usual intergrading. F 9 was duplicated ; one batch (from light, well-lined 

 parents) yielded 17 specimens, variable from pure light (though not intensely 

 white) to intermediate, 11 or 12 having the lines rather strong ; the other 



