CERTHIID^E—CERTHIIN.E: TYPICAL CREEPERS. 



279 



of the genus CUmacteris ; while the genus Certhia, with 5 or 6 species or subspecies, and cer- 

 tain allied genera (all but one Old World) constitute the 



Subfamily CERTHIIN>E: Typical Creepers. 



Our species may be known on 

 sight, among North American Cs 

 cines, by its rigid, acuminate tail- 

 feathers, like a Woodpecker's. Be- 

 sides : bill about equal in length to 

 head, extremely slender, sharp, and 

 decurved ; nostrils exposed ; no rict.il 

 bristles; tarsus scutellate, shuitti 

 than 3d toe and claw, which is con- 

 nate for the whole of the 1st joint 

 with both 2d and 4th toe; lateial 

 toes of unequal lengths ; 1st toe 

 shorter than its claw ; claws all 

 much curved and very sharp ; \a ing 

 10-primaried, 1st primary very shoit, 

 not i the 2d, which is less than 

 3d ; point of wing formed by 3d, 4th, 

 and 5th ; tail rounded, equal 1o oi 

 longer than wing, of 12 stout, elastic, 

 curved, acuminate feathers. Rest- 

 less, active, little forest birds that 

 make a living by picking bugs 

 out of cracks in bark. In scram- 

 bling about they use the tail as Woodpeckers do, and never hang head downward like Nut- 

 hatches. Lay numerous white, speckled eggs ; are not regularly migratory ; have slight 

 seasonal or sexual changes of plumage; are chiefly insectivorous, and not noted for musical 

 ability. 



CERTHIA. (Lat. certhius, a creeper. Fig. 141.) Characters as above. The stock-form 

 of this genus varies according to locality. European varieties sometimes recognized are 



C. cost(E and C- britannica. The N. Am. bird, 

 when separated from the European, has been called 

 C. nifa (Bartram, 1791), fitsca (Barton, 179!)), 

 and americana (Bp. 1838), for Eastern specimens; 

 C. montana for those from the Rocky Mt. region ; 

 C occidentalis for those from the Pacific coast 

 region ; and C. meocicana (or alticola) and C. 

 albescens for the Mexican forms. The differences 

 between any of these forms are slight; but if they 

 are to be recognized by name, all the American 

 ones must be specifically separated from those of 

 Europe ; for we adopt the fact of intergradation, not any degree of difference, as our touchstone 

 of subspecificality, and it is a physical impossibility for any of our creepers to intergrade now 

 with any European ones. Therefore our birds should stand as C- americana, C a. montana, 

 C- a. occidentalis, and C. a. albescens. But I forbear to make the change, in deference to the 

 A. 0. U. committee over which I had the honor of presiding in our attempts to confer immu- 

 tability upon nomenclatural permutability. 



Fig. 140. —Common Brown Creeper, Cnihia famthai-is, nearly 

 nat. size. (From Brehm.) 



Fig. 141. — Head, foot, and tail-feather of Cer- 

 ifiin, nat. size. (Ad. nat. del. E. C.) 



