APPENDIX TO OSCINES. 227 



that the examinatiou of a large number of specimens has resulted in his accepting a 

 much smaller number of species than bad previously been received as valid, and sig- 

 niticautly adds that, had a still more complete series been before him, he would probably 

 have reduced the number still further. So then, in his mind, recognition of specitic 

 rank is something almost dependent upon the number of specimens one has for com- 

 parison — the larger the series, the fewer the species.* Another cfiualiy well-known 

 author, in a recent review of the fifteen species of the genus Ccrthiola, remarks that " it 

 is a nice (piestion what are really species in this genus, and what merely races or varie- 

 ties, but it would probably be not far Irom correct to assume that the various forms 

 described are simply moditications of one primitive species, produced by geographical 

 distribution and external ])hysical conditions." Is there any reason to suppose that, 

 since the primitive species has become thus modified by geographical distribution and 

 external physical conditions, that it was not, itself, one of the niodiiications of a still 

 more primitive form ? Yet the progenitors of this "primitive species," which has split 

 into no less than fifteen different races, must have undergone variations brought about 

 by changed geographical habitats and different physical conditions ; unless, iudeeil, 

 they were special creations, and confined to a single narrow locality, a supjiosition 

 which we have quite as much reason for ap[)lying to all the recent forms of Ccrlltiolu as 

 to the one original form. 



In considering the question of specific distinction, too little importance has been 

 attached to the habits and notes of the different races, while there seems to be no iu- 

 trinsic reason why a difference in these points should not be considered of as much weight 

 as a variation in the plumage. A series of Meadow-larks may be laid out, represent- 

 ing a gradual transition between the Eastern and Western forms, yet the notes of the 

 two are so different that, in a region where they both abound, either may be distin- 

 guished at onct! by its voice ; and a bird whose song is iiatermediate between the two, 

 is so rare that, in a residence of two years in a region where both were abundant, I 

 never heard one. Here, then, is an instance where the different forms may always be 

 distiuguisluHl by their notes, though sometimes ambiguous in their plumage. Again, 

 Coniopus richardsoiiii resembles Sayoynis fiiscus in its habits more than it does the Wood 

 Pewee, C. vlrens, while its notes are as different from those of the latter bird as the 

 western Lark's are from the eastern's. If Macgillivray's Warbler is a geographical 

 variety of the Mourniug Warbler, it is difficult to comprehend how it could have suf- 

 fered such a complete loss of musical power, seeing that its liabits are unchanged, and 

 that the external physical intluences are very nearly similar. Perhaps, however, the 

 "dry, thin air" can account for it; but if this is the case, it would be interesting to 

 knrnv why the same air has failed to change the voices of the Robin and Hermit Thrush 

 in the sligiitest degree.! All the western species whicli are closely allied to, or inter- 

 grade with eastern forms, varj^ from the latter, more or less, in their notes and habits, 

 sometimes so nuich that a resemblance can scarcely be recognized. That this may be 

 partly due to changed conditions of life, is undeniable, yet, under the supposition that 

 it has been wholly brought about by such cause, it is very dithcult to see why the same 

 changes have effected opposite results in birds of the same family and of the same mode 

 of life. And if these supposed races are found to meet and occui)y the same regions, 

 each i)reserving its peculiarities of notes, plumage, and habits, with a great degree of 

 C(mstancy, how can they properly be called " geographical" varieties, or their differ- 

 ences be accounted for on the supposition of different physical conditions 1 Yet of one 

 species, at least {StitrtteUa mayna), this is absolutely true. And admitting the in- 

 fluence of these external causes to be sufficient to produce such results, the (|uestion at 

 once arises: How wide must be the gap that separates congeneric " species ;" where 

 shall the limit of variation produced l)y such causes be placed ? 



But however ornithologists may differ as to the proper rank of these forms, their 

 existence is uiuleniable, whether classed as species, varieties, or races, and it becomes 

 necessary to distinguish tiiem apart in ornithological nomenclature. The usual method 

 is to give the name of the first-discovered race, together with the siiecific title of the 

 form rciferred to as a variety. Thus, iNIacgillivray's Warbhu' is spoken of as (icolltli/pis 

 phUadelphia var. macgUlirraiji. To follow out this method, every bird of which there is 

 nu)n! tlian a single form should be designated by tLreeJ: names, generic, specific, and 



* Quite true. We can only predicate and define species at all from the mere circum- 

 stance of mwsiHi/ /ikA.s. "Species" are the twigs of a tree separated from the parent 

 stem. We name ami arrange them arldtiarily, in default of a means of reconstructing 

 the whole tre<; according to nature's raniilicalious. — E. ('. 



t Is it not (piite reasonable to suppose that dilieri-ut aninuils may possess a difl'orent 

 degree of su.sceptilnlity to nio<lifyiug influences, and that some nuiy be al)le to resist 

 such iidluences altogether? We must not presume upon uniform plastictity of orgaui- 

 zatiou. — E. C. 



tl strongly .advocate a return to jtolyuomial nomenclature, as the only lit instru- 

 ment of expression of nice shades of zoological meaning. Many of us, in I'tVect, arc 

 already using trinomials, the true nature of which is but iiaitially concealed by inter- 

 vention of the term •' var." — E. C. 



