530 MR. L, DONCASTER ON COLOUR-VARIATION [ Dec. 12, 
found that of the males 81 per cent. were spotted with dark 
undersides, 19 per cent. striped only with light undersides. I 
found rather over 83 per cent. spotted and dark, 16 per cent. 
striped and light, and about 0°5 per cent. with intermediate under- 
sides. Of the females, | found 27°5 per cent. with dark under- 
sides, the same proportion as was observed by Bateson. The 
occurrence of the different varieties is in every way in close agree- 
ment with that found by Bateson; and it may be concluded that 
their distribution at that season has not changed appreciably in 
ten years. J did not collect in the Darro valley from which 
Bateson’s second sample was obtained, but I found that on the 
lower slope of the hill towards the Genil valley the proportions 
did not differ from those on the top. On the Darro slope of the 
hill, which is very steep and faces north, the beetle did not occur, 
although Spartiwm was abundant. 
At Granada a considerable proportion of the beetles were in 
cop., and I collected 119 couples and recorded the characters of 
each as they were gathered. Care was taken to see that they 
were really paired, and since 71 pairs remained coupled after 
they were dead in the killing-bottle, there can be little doubt 
that all or nearly all were really iz cop. ‘Table II. gives an 
analysis of these. Of the 119 pairs, there were 22, or over 18 per 
cent., in which both male and female were striped green with 
light undersides. Taking pairing at random among the general 
population the expectation would be 10°5 per cent. But the pro- 
portion of males of this type which were paired is considerably 
higher than in the general population (29 out of 119 or 24:4 per 
cent.); so that random mating out of those paired would give 
17 per cent. of such pairs, which does not differ greatly from the 
18 per cent. observed. Similarly there were 25 pairs (21 per 
ce t.) in which both male and female were red with dark under- 
sides. The expected number on random mating among the whole 
population is 15:2 per cent., on random mating among those 
actually found paired about 17 per cent. The numbers observed 
are of course much too small to give reliable conclusions, but they 
indicate that of the males of the green striped form, and females 
of the red spotted form, a slightly higher proportion is found 
paired than in the general population, and that there is possibly a 
very small tendency towards selective mating between individuals 
of the same colour type. 
At Ronda Spartiwm bushes were very scarce, and upon many 
there were no beetles, so that altogether only 106 individuals 
were obtained, 80 of which were males, 26 females. Although 
these numbers are small, they indicate that the population differs 
considerably from that of Granada (Table IIT.). Of the males 
60 (75 per cent.) were spotted and dark underneath, 9 were 
green, striped and light, one red, spotted and striped, light, and 
10 red, spotted and striped, with intermediate undersides. At 
Granada only 6 intermediates occurred in 1382 specimens; while 
