MUSEUM OF COMPARATIVE ZOOLOGY. 255 



as though it was in his opinion doubtfully distinct, and observes that, " if 

 really distinct, is so closely allied to T. Pallasi as to render a separa- 

 tion of the two exceedingly difficult." The T. Pallasi was formerly 

 recognized as inhabiting California by good authorities. Dr. Ganibel, in 

 his " Remarks on the Birds of Upper California," etc.,* after stating that 

 '•the dwarf thrush of Audubon was founded upon specimens from the 

 Atlantic States, and no doubt upon the true hermit thrush," remarks : 

 "An examination of specimens of the T. minor [=T. Pallasi] from the 

 Atlantic and Pacific coasts of North America shows no difference in 

 any way, except that perhaps the western one is somewhat smaller, yet 

 the difference is scarcely appreciable. From the measurement of many 

 western specimens I found its length to be 6^ inches, and the extent of 

 wings 10^ inches; the tail, wings, and relative length of quills the same as 

 in our eastern one, and, in fact, I think it can in no possible way be dis- 

 tinguished as specifically different." California specimens, however, seem 

 to average a little smaller than New England ones, so that the T. nanus 

 seems best entitled to recognition of any of the several disputed forms of 

 this group. 



The habits of T. nanus, as described by Dr. Cooper, are exactly like 

 those of the T. Pallasi of the East, except in regard to the situation of its 

 nest, Jus account of its nest and eggs according exactly icith those of T. 

 Swainsoni, and not at all with those of T. Pallasi, its nearest ally.f 



The Tardus Auduboni of Baird, of the Rocky Mountains, I have already 

 also referred to T. Pallasi, from average specimens of which it differs 

 only in being slightly larger. My reasons for this opinion have been given 

 with sufficient detail elsewhere. % 



It is difficult to reconcile the account given by Wilson, § and corrobo- 

 rated by Audubon, || of the breeding habits of this species with what is 

 now known of the distribution in the breeding season of this group (sub- 

 genus Hylociclda) of thrushes. The account given by these authors of the 

 situation and structure of the nest is applicable to only T. Swainsoni, 

 which, as well as the T. Pallasi, is not known to breed so far south by 

 several hundred miles as the localities they give. The only species which 

 may probably breed there is the T. fuscescens ; but this species does not 

 nest on trees. To determine to which species of thrush these authors refer 



* Proc. Phil. Acad. Nat. Sci., Vol. Ill, p. 14, October, 1844. Also Journal Phil. Acad. 

 Nat. Sci., 2d Series, Vol. I, p. 41, 1847. 



t According to Professor A. E. Verrill, the T. PaUasi nests on the ground, and lays 

 " bright-blue " eggs. Proc. Essex Inst, Vol. Ill, p. 145. 



J Mem. Bost. Soc. Nat. Hist, Vol. I, p. 012. 



$ Am. Orn., Vol. V, p. 91. 



|| Orn. Biog., Vol. I, p. 303: Bird; of America, Vol. Ill, p. 30 



