( cxxxv ) 



not yet been able to ascertain exactly what constitutes a 

 " good dudu night,' but it must be calm and warm, and I 

 think unsettled : a clear starlight night is not so good. How 

 interesting it would be to make huge collections every night 

 and correlate the different groups with minutely recorded 

 meteorological data ! 



" Now a few other observations from my journal. 



"Attractiveness of exudate from trees. — On Nov. 11 and a 

 few days before and after I noticed a minute moist patch 

 about a centimetre square on the bark of a tree which was 

 very attractive to Hymenoptera and Charaxes. I caught 

 three specimens of brilliant green Ampulicinae of at least 

 two species, in succession, and Pompilidae also freemen ted it. 

 It was presumably caused by a fungus disease. Another day 

 a very sickly-looking stem of a sapling about 3 feet high 

 was so attractive to Charaxes that half a dozen specimens 

 of different species visited it at once, and probed- it eagerly 

 with the proboscis. After a clay or two it proved less attrac- 

 tive, but some fine Cetoniidae came to it : when gum began 

 to exude it was no longer attractive. 



" Mutilloid Spider. — I sent you a year ago from Ndala a 

 Mutilloid spider [see p. xcvii], and now send a second specimen 

 like the first, with red thorax and black abdomen with four 

 large white spots. As in the first instance, it momentarily 

 deceived me as it ran along in a very Mutilloid manner. 

 But when alarmed it scurried away in a typically spicier 

 fashion. 



"' Ammophila lugubris, Gerst. — I sent you some notes on a 

 very unskilful or inexperienced specimen of this Fossor from 

 Ndala, about a year ago [Proc. Ent. Soc, 1917, pp. xlii-xliv, 

 where the specimen is referred to beninensis, Pal. de Beau v.]. 

 A species which seems the same is common here now. On 

 Nov. 26, on the kopje, as 1 strolled along, watching for 

 butterflies, 1 saw on a Low shrub at my feet one of these 

 Ammophila bahaving in a very curious manner. It was 

 straddling a small stem and every now and then excitedly 

 grasping it in its mandibles, as if it were a caterpillar. The 

 reason for this was soon seen, for after a few minutes she Hew 

 to the ground at my feel and picked up her larva, which 



