( lxxviii ) 



It was, however, possible that the discrepancy was due to a 

 difference between Singapore Island and the nearest main- 

 land, and Prof. Poulton hoped that Dr. Hanitsch would be 

 able to settle the matter by collecting on the mainland as 

 well as a further series on the island. Different observers 

 had given very different estimates for Hong Kong, and here 

 too it was hoped that indiscriminately collected specimens or, 

 better still, the imagos reared from indiscriminately collected 

 larvae would show what are the actual proportions. 



Specialisation in the response of Butterflies to 

 stimuli. — Prof. Poulton drew attention to an observation 

 an Agriades thetis (bellargus), Rott., made September 12 of this 

 year on the steep slopes of Maiden Castle near Dorchester. 

 He found that when a butterfly was carefully approached so 

 that it was evidently unaware of the presence of the observer, 

 it could be gently tapped or stroked with the feathery end of 

 a long grass stem without causing it any alarm. Often, when 

 thus disturbed, a butterfly would fly a few inches and then 

 return to the same flower-head. It was evident that such 

 stimuli, which would continually be caused by the wind under 

 natural conditions, were sharply distinguished from those 

 normally caused by possible enemies. It was, of course, only 

 what we should expect, but it was interesting to obtain the 

 experimental demonstration in so simple a way. 



A Gynandromorphous Ant. — Mr. Donisthorpe exhibited 

 an ergatandromorph of Myrmica laevinodis which he had 

 taken in his garden at Putney on October 11. It was very 

 like an ordinary worker in appearance, but by the curious 

 jerky manner in which it walked he at once saw there was 

 something strange about the insect. Under the lens it is 

 seen to have a single ocellus (the left lateral one), the meso- 

 thorax enlarged on one side, a long spine on the left side of 

 the epinotum and a very short one on the right. The gaster 

 shows five segments and is mostly black, and the legs are 

 striped with black. This is the 35th known gynandro- 

 morphous ant in the world, the 6th Myrmica, the 9th British 

 specimen, and the 8th described by the exhibitor. 



Mermithogynes of Lasius flavus and L. alienus. — 

 Mr. W. C. Crawley exhibited mermithogynes of Lasius 



