Recently published Ornithological Works. 207 



is believed to have been first introduced by the late Mr. Rhodes, 

 has during the last few years completely established itself in 

 Cape Town and its suburbs, nesting abundantly in similar 

 sites to those made use of in England. Passer domesticus, 

 on the other hand, has (happily) not yet reached the Cape 

 (where its place is taken to a certain extent by P. arcuatus), 

 but it is said to have been introduced at Durban, and to be 

 increasing there " very rapidly." 



Many notes on the nomenclature and arrangement of birds 

 in the South-African List will be found in this part of the 

 memoir. 



27. Scott (IV. E. D.) on the probable Origin of certain 

 Birds. 



[On the probable Origin of certain Birds. By William E. I). Scott. 

 Reprinted from ' Science,' n. s. vol. xxii. no. 557 (September 1, 1905).] 



In the List of North-American Birds it is well known that 

 there are certain species, described by Wilson, Audubon, and 

 others of the older writers, of which but one or two examples 

 have ever been obtained. It can hardly be supposed, seeing 

 the energetic and careful way in which every part of the 

 Nearctic Region has now been searched by modern observers, 

 that any more representatives of these species will ever be 

 found, and they may be safely regarded as extinct. Mr. Scott 

 selects seven of them, such as Tringa coo-peri and Spiza towns- 

 endi, and discusses their relationships. He comes to the con- 

 clusion that they are" mutations," which were not perpetuated, 

 or what are sometimes called " sports," of existing species. 

 On the other hand, two recently discovered forms, Helmintho- 

 phaga leucobronchialis and H. lawrencii, which are usually 

 regarded as hybrids, and were quite unknown in the days of 

 Audubon and Wilson, Mr. Scott considers to be recently 

 produced "mutations" which are increasing in number. 



As regards the first of these hypotheses, we are disposed 

 to agree with Mr. Scott, but as regards the second, more 

 evidence, as Mr. Scott confesses, is required. 



The "strange case of Athene chiarad'ue" (sec 'Ibis/ 1903, 



