2 Transactions of the South African Philosophical Society. 



and gleaned some further information from the discoverers of the 

 various nests. 



The main point in which all observers * agree is this, that during 

 incubation the female is a prisoner in a kind of cage, the entrance to 

 which is closed to such an extent that it has to be broken open 

 before the female can leave the nest. In all cases with which I 

 have become acquainted the birds selected a hollow tree to make 

 the nest in. Mrs. Barber says that they may also make the nest 

 " between the crowded stems of the tall Euphorbia." However, I 

 cannot reconcile this statement with the succeeding sentences in 

 Mrs. Barber's account, to which I shall refer again presently. In 

 the country of the Hereros, Pechuel — Losche found a nest in a small 

 cleft of a rock which had also been closed up to form a kind of cage. 

 In our neighbourhood the birds do not seem to be very particular 

 about the kind of tree they choose as long as it is suitable for their 

 purposes. I have seen four nests made in the stem of Euphorbia 

 grandidens, one in the stem of Sideroxylon inerme, one in the stem 

 of Schotia speciosa, and one in the stem of another kind of tree 

 which I could not identify. The essential points in guiding the 

 birds in their selection seem to be only whether the hollow part 

 of the stem is sufficiently large for the female to move about in the 

 nest, and whether it has one or more comfortable entrances, which 

 lastly must be of such a nature that they can be partially or com- 

 pletely closed up. The female, when once inside the nest, is fed by 

 the male either through a narrow slit left in the material with which 

 the entrance has been closed or through a natural cleft in the wood. 

 In the latter case the main entrance is closed up completely. Mrs. 

 Barber also states " that while the process of incubation is going on, 

 the male bird builds the female into the nest, closing up the entrance 

 in such a manner that it is impossible for her to escape, leaving only 

 a small hole for the purpose of feeding her during her long im- 

 prisonment." " This peculiar habit may be a precautionary measure 

 to protect the female during the season of incubation ; for it may be 

 that during that time she is too weak and dull to fly away from any 

 approaching danger." It will be seen at once that these statements 

 can scarcely be reconciled to Mrs. Barber's previously mentioned 

 statement that the nest is sometimes formed between the crowded 

 stems of the tall Euphorbia. I have further to question the state- 

 ment that the male builds the female in. Livingstone was told so by 

 a native, but I have not come across any evidence that this is 



* See Mrs. Barber's account in ' The Birds of South Africa,' by E. L. Layard, 

 new edition by R. B. Sharpe, p. 128 ; also Livingstone's, Kirk's, and Anderson's 

 observations in ' Brehm's Tierleben,' Neue Ausgabe, 1891, vol. v. p. 13. 



