362 



SNODGRASS AND HELLER 



lary stripes are lost. The first branch includes the races inhabiting 

 Tower, Abingdon, Bindloe and Culpepper; the second those races in- 

 habiting Indefatigable, Barrington, Wenman, James, Albemarle and 

 Narboro. 



We have four adult specimens from Chatham taken May 23. 



MEASUREMENTS OF ADULT SPECIMENS OF NeSOmtniUS udaiHsi. 



79. THE NESOMIMUS PERSONATUS SERIES. 



Rothschild and Hartert have grouped all the forms of Nesomimus ex- 

 cept N. trifasciatus^ N. m.acdonaldi and N. adamsi under one species 

 iV^. melanotis. We think, however, that two groups instead of one 

 can be distinguished, of which one, N. personatits^ inhabits the more 

 northern islands of the archipelago — Tower, Abingdon, Bindloe and 

 Culpepper ; while the other, N. 7nelanotis^ inhabits the central islands 

 — Barrington, Indefatigable, Jervis, James, Albemarle and Narboro, 

 and also Wenman, lying to the north. 



The differences between N. personatus and N. melanotis are slight, 

 but the former is characterized by a blackish tone to the central areas 

 of the feathers rather than a brownish. In some cases the general 

 shade of the upper parts in N. personatus may be even lighter than 

 in A^. fnelanotis^ but the light color is due to the marginal areas of the 

 feathers, the central parts in such cases being blackish. 



JV. personatus is represented by a different subspecies on each 

 island where it occui's. Of these the one on Abingdon was described 

 first and hence must give its name to the group. The Tower sub- 

 species, however, resembles the Chatham species, N". adajnsi, more than 

 does any of the others, so with it we begin the species. 



79a. NESOMIMUS PERSONATUS BAURI (Ridgway). 



Nesomimus bauri Ridgway, Proc. U. S. Nat. Mus., xvii, p. 357, 1894 

 (Tower Island) ; Proc. U. S. Nat. Mus., xix, p. 492, 1896. 



Nesomimus 7ne/anoiis dauri ROTHSCniLn and Hartert, Novit. Zool. , vi, p. 

 145, 1899. 



Ranjre. — Tower. 



