1905.] IN THE BEETLE GONIOCTENA VARIABILIS. 529 



The case is of peculiar interest not only on account of the 

 great variability in a single species, but esj^ecially because of 

 the rather close correlation between the two chief colour-types 

 and the two sexes. Bateson found that on the hills behind the 

 Alhambra at Granada 80 per cent, of the males were spotted and 

 dark below, and over 70 per cent, of the females unspotted and 

 light. In the Darro valley, perhaps a cotiple of miles away, only 

 62 per cent, of the males were dark, and 85 per cent, of the 

 females were light ; i. e. there was a much higher proportion of 

 light specimens in each sex. On the other hand, at Castillejo, 

 near Toledo, rather early in the season, of 75 specimens all were 

 dark and spotted, all but one being males. There was therefore 

 some indication that the proportions vary with the locality, or 

 possibly with the season ; and it seemed important to determine 

 whether the correlation between variation and sex was a genuine 

 and permanent phenomenon, or was more or less accidental, 

 depending on the local and seasonal conditions at Granada. I 

 therefore took the opportunity, during a visit to Southern Spain 

 this spring (1905), of collecting Gonioctena in various localities, 

 in the hope of settling this question. 



I found that Spartiimi retama, upon which the beetle lives, 

 grew abundantly in most of the hill}'- uncultivated districts I 

 visited, except in the neighbourhood of Gibraltar, where I imagine 

 that the rainfall is too great, and in the desert to the east of 

 the Sierra Nevada, which is almost wholly without vegetation. 

 Almost everywhere where I found the Sj)arti;um I found also 

 Gonioctena, but never saw it on any other plant. Where the 

 beetles were abundant they were beaten into a net, but when 

 they were scarce it was necessary to search carefully for them 

 and catch each one separately. This probably leads to a slight 

 excess of reds in my samples, since they are much more con- 

 spicuous ; but when this method was adopted the bushes were 

 searched very thoroughly, and I believe that the error may safely 

 be disregarded. On one occasion one method was used in a 

 particular localit}^, and two days later the other was tried in the 

 same place ; and the difference in the proportions of red and 

 greens was not more than about 3 per cent., which might easily 

 have been due to chance in a comparatively small sample. 



I collected the beetles at Ronda, Granada, and in two oi- three 

 localities in the neighbourhood of Malaga ; those at Ronda were 

 obtained on March 23-24, at Granada March 25 and 28, and 

 collections were made at Malaga at the beginning of April and 

 again towards the end of the month. It will be most convenient 

 to describe the Granada collection first. On the hills behind the 

 Alhambra, between the Genii and Darro valleys, Gonioctena was 

 exceedingly abundant, and I collected altogether 1382 specimens, 

 978 males and 404 females (Table I.). In the distribution of 

 the different varieties they agree remarkably closely with those 

 obtained by Bateson ten years ago in the same place. Bateson 



