Resemblance of South Africaji Birds. 1 1 



instances in brief detail to illustrate my meaning, and prove 

 my theory. On 30th July, 1898, whilst out shooting, I put 

 up from almost under my feet an Eagle-Owl. It settled a 

 short distance ahead, so I followed it. When I reached the 

 spot I conunenced searching for the bird, and after some 

 minutes succeeded in flushing it again, but very nearly 

 treading on it in so doing. This invisibility of the Owl 

 somewhat puzzled me, so I determined I would see it on the 

 ground before firing at it. I followed this bird from place 

 to place for over half an hour before I could see it clearly 

 enough to be sure of its identity, and then even it was more 

 its "ears" — momentarily erected — that betrayed it, as, 

 although it was only sitting amongst the grass-tufts, I could 

 not make out anything like the outline of an Owl, so beau- 

 tifully did the tints of its mottled grey and brown plumage 

 harmonize with the surrounding grass and stones. It was a 

 clear case of " protective resemblance,'' as had the bird been 

 of any other colour — red, green, or black, for instance — 

 I must surely have seen it repeatedly from a much greater 

 distance than I was from it when it was flushed. I have 

 noticed this fact repeatedly since, but will only relate one 

 other instance in further defence of my assumption. On the 

 18th October, 1903, I found a nest (if such the depression in 

 the soil can be termed) of this species on a ledge or plaiform 

 in a rocky hollow. This ledge was covered wiih ground on 

 which several of the ordinary veld plants grew. I flushed 

 this bird from her two eggs quite suddenly and was certainly 

 not more than 10 feet distant when it flew up. 1 returned 

 to the spot later with my camera, but in trying to get it 

 properly fociissed on the bird had perforce to drive it up to 

 find its exact locality. I was aliove the Owl's position at the 

 time and would have seen it e:isily enough but for its 

 assimilative coloration. When the bird settled again I 

 immediately lost sight of it, and althouffh it was onhj partially 

 screened hy the herbage I had to use my glasses to be sure of 

 its identity. I took particular notice of this case, remem- 

 l)ering Mr. Distant's friendly criticism. That Owls are 

 subject to dimorphism is a well-known fact. Professor 



