134 THE SCOTTISH NATURALIST 



taken at this and other lights. Considerable variation as regards 

 both colour and size was noticeable in this species. On the whole 

 the specimens were distinctly darker and greyer than the type, and 

 not a few were almost uniform black. Typical examples were, 

 however, far from scarce, and some of even a paler tint occurred. 

 On occasions when a substantial number of examples were secured, 

 all the varieties were usually represented. A still more variable 

 species was Orthosia lunosa (Lunar Underwing). Among those 

 taken at the Isle of May heavily darkened specimens were common, 

 while some were pale buff, and others again of a distinctly reddish 

 tint. The same variability was encountered in the case of Noctua 

 xanthographa ; indeed, it would have been hard to recognise some of 

 the specimens had they occurred by themselves. Perceptible varia- 

 tion was also observed among the large number of Phisia giwivia 

 collected. A few were noticeably paler or more silvery looking than 

 the type, while some were of a richer, almost reddish-brown tint ; 

 but whether there is any significance in this from the migration 

 point of view, it is difficult to say. 



This being a first report, with the prospect of others to 

 follow, it would be premature to attempt to draw conclusions 

 at present from the records. One or two facts, chiefly of a 

 statistical nature, may, however, be here adverted to. Up to 

 the end of 1914 the number of insects, that is of individuals, 

 obtained from a dozen Scottish lighthouses was roundly 

 7500.^ The species represented by these number 241 ; of 

 which 161 are Lepidoptera (2 Butterflies and 159 Moths), 18 

 Caddis-flies and Lacewings, 40 Two-winged Flies (Diptera), 

 10 Beetles, and 12 of other orders. It is usual to think of 

 Moths alone as night-fliers, and attracted by lights, but the 

 above shows that not a few other insects have similar habits 

 and are similarly attracted. This is a point of considerable 

 importance. Both sexes come to the lanterns, but as a rule 

 males predominate ; in the case of certain Moths the pro- 

 portion works out at between 2 and 3 to i. Whether this 

 signifies an actual inherent preponderance of males, or merely 

 that they fly about more than the females, is a moot point. 

 Personally, I incline to the former as the explanation in a 



' Exclusive of over 2000 gnats (p. 38). Certain of the figures appear- 

 ing on previous pages require readjustment owing to additional 

 specimens having been received in the latter part of 19 r4. 



