174 MR. P. L. SCLATER ON BIRDS FROM BARBADOES. [Mar. 3, 



together ; the progenitors of all the species of Molothrus may have 

 been early infected with this habit, and inherited with it a facility 

 for acquiring their present one. M. pecoris and M. bonai-iensis, 

 much as their instincts differ in some points, are both parasitic 

 on a great number of species — M. rufoaxillaris on M. badius ; 

 and in this species two or more females frequently lay together. 

 Supposing such a habit as of two or more females very frequently 

 laying together in the M. bonariensis when it was a nest-builder, 

 or incubated its own eggs in the nests it seized, the young of 

 those birds that oftenest abandoned their eggs to the care of an- 

 other would probably inherit a weakened maternal instinct. The 

 continual intercrossing of the birds with weaker and stronger in- 

 stincts would prevent the formation of two races differing in habit ; 

 but the whole race would become deteriorated and decline, 

 and would only be saved from final extinction by some indivi- 

 duals laying occasionally in the nests of other species, perhaps 

 of a Molothrus, as M. rufoaxillaris still does in the nest of M. 

 badius, rather than of birds of other genera. Certainly in this way the 

 parasitic instinct may have originated in the M. bonariensis with- 

 out that species ever having acquired the habit of laying and incu- 

 bating in the covered dark nests of other birds. 1 have supposed 

 that they once possessed it merely to account for their strange 

 partiality for such nests, appearing, as it does to me, so much like 

 recurrence to an ancestral habit. 



2. On a small Collection of Birds from Barbadoes, West 

 Indies. By P. L. Sclater, M.A., Ph.D., F.R.S., Secre- 

 tary to the Society. 



[Eeceived February 5, 1874.] 



I have the honour of exhibiting a small collection of birds from 

 Barbadoes, West Indies, which has been transmitted to me in spirit 

 by Sir Graham Briggs, F.Z.S. The only authority on the birds of 

 this island at present is the unsatisfactory nominal list given by Sir 

 Robert Schomburgk in his ' History of Barbadoes ' (London, 1847), 

 p. 680*. 



The collection forwarded by Sir Graham Briggs contains speci- 

 mens of the following species. 



1. Dendrceca petechia (Linn.). 

 A well-known Antillean species. 



2. Certhiola martinicana (6m.). 



The Certhiola of Barbadoes appears to agree best with that of 



Martinique and S. Lucia, but shows hardly any of the characteristic 



white on the middle of the throat, as do my specimens from the 



last-named island. As, however, my single skin from Barbadoes has 



* Cf. P. Z. S. 1871, p. 267. 



