i6o 
Jeffries on the Primaries of Birds. 
little feathers lie one over the other and, owing to their small size, 
apparently on the shaft of the first developed primary. The same 
condition is found in the young of Goniaphea ludoviciana , and 
Sialia sialis. Passer do?nestica differs in that the first primary 
is in due proportion to the first covert. 
This proves that the “first little feather” is nothing but the 
covert to the first developed primary and that the “ second little 
feather” is an undeveloped primary. 
There is no room for doubt about the homologies of the pa- 
pillae, and the feathers are nothing but parts of the papillae. The 
second and subsequent sets of feathers are developed from buds 
of the original papillae, much after the manner of teeth, and 
hence are equally determinate with the original papilhe from 
which they spring. 
If we examine a ten-primaried Oscinine bird we find the same 
condition of things as in the nine-primaried, except that the 
first primary papilla is of good size. Of this condition of things 
the fledglings of Proglodytes a'edon and Mimus carolinensis 
are good examples. So the formula for a nine-primaried and a 
ten-primaried Oscinine bird is the same. The number of feathers 
can be represented as follows, “ ab.” standing for aborted, and a 
minus sign indicating a feather belonging to a series of the fore- 
arm beyond the carpus : 
Melospiza melodia : Pr., i ab., 2 — 10 ; pr. c., 2 — 10. 3rd row, 
7. Sec., 9, sec. c., — 1,2 — 11, 3rd row, 8. 
Mimus carolinensis : Pr. 1 — 10, pr. c., 2 — 10, 3rd row, 7* 
Sec., 9, sec. c., — 1,2 — 11, 3rd row, 1 — 6. 7 — 8 small. 
To this rule Corvus americanus forms an exception, since it 
seems to have ten primary coverts. 
Passing to the Clamatores , the King Bird ( Tyrannus car- 
olinensis) , will be taken as an example. Here the fore-arm 
remains nearly the same, even in respect to the auxiliary feathers, 
but in the hand we find a first covert beyond the first primary and 
another corresponding feather added to the third row. So the 
formula for Tyrannus carolinensis is : Pr., 10, pr. c., 10, 3rd row, 
8 ; sec., 9, sec. c., 10 — 1, 3rd row, 9. 
In the fledgling of Chcetura pelasgica we find the following- 
formula : Pr., 10. pr., c. 10, 3rd row-, 8, sec., 9. sec. c., 10 — 1, 
3rd row 7. Besides these there are several more rows. 
In the adult Trochilus colubris there are ten primaries and 
