62 PTERYLOGRAPHY. 



stem by a single row of feathers. Outer branch quite free, but narrow, with a hook of a single 



row of feathers at its extremity ; main stem somewhat dilated near the branch. Lumbar tract 

 perceptible, but weak. 



b. With feathered tarsi. 



F. tyrannus TEMM., PL Col., 73. Both eyelids with weak eylashes. Twenty-jive remiges : 

 the first five graduated, the differences being uniform and small ; the first remarkably short, the 

 fifth the longest, the sixth shorter than the fourth, the seventh longer than the third. Pterylosis 

 as in the preceding species, but with all the tracts rather broader, and both the inner and outer 

 branches of the inferior tract shorter. Dorsal portion of the spinal tract very weak. 



4. CYMINDIS. 



The two species of this group examined by me, namely, F. hamatus TEMM., PL Col., 61, 

 and F. uncinatus TEMM., PL Col., 103, 104, and 115, differ but little in their pterylosis from 

 Buteo ; indeed, only in the fact that the outer branch of the pectoral inferior tract is placed very 

 close to the stem, and is somewhat more connected with it at the base. All the tracts are narrow, 

 but otherwise without anything remarkable about them. The wings, which extend nearly to the 

 end of the tail, consist in F. hamatus of twenty-Jive, and in F. uncinatus only of twenty-three 

 remiges, of which the first is as long as the seventh, the second is nearly equal to the sixth, but 

 stiU a little shorter indeed, just as much as the third is shorter than the fifth, and the fourth is 

 the longest. The first has a very strong and deeply seated angular emargination, of which a 

 slight indication appears on the two following primaries. This group is, however, best distin- 

 guished from the Buteones by the want of the connecting membrane between the toes, and the 

 notching of the sharp inner margin of the middle claw. 



5. POLYBOR.US (Caracara, Cuv.). 



The nearly-naked face and the strongly-developed eyelashes distinguish this group from the 

 preceding, and show its near relationship to the following one, which approaches very closely both 

 to Polyborus and to Morphnus. 



1. F. aterrimus, TEMM., PL Col., 37 and 342. Twen ty- two remiges : the first somewhat 

 shorter than the seventh, the second somewhat longer than the sixth, the third having the same 

 proportion to the fifth, the fourth a little longer than either of them ; the primaries generally very 

 long, and the remiges of the arm very short ; first four primaries with a diminution of the inner 

 vane. 



Pterylosis with no peculiarities ; all the tracts narrow, but the outer branch of the inferior 

 tract broader and quite free, with a strong hook at the end. Dorsal portion of the spinal tract 



