Genus— R OSSORNIS. 
Rossornis Mathews gen. nov. , . . . . . . . Type R. macrnrus, 
Caprimulgine birds of medium size, with, small bills with huge gape, long 
wings, long tails and very small legs and feet. 
The bill has a small flat tip, triangular with culmen keeled and sides flattened : 
the tip is decurved, bluntly hooked. The nostrils exist as circular tubular 
apertures situated on each side of the culmen near the base. The lower 
mandible is very flat with extensive rami, the tip very small and spoon-shaped, 
fitting into the tip of the upper mandible. There is a row of strong projecting 
bristles along the upper edge of the gape. 
The wing is long with feathers broad and inner-webs fringed : the outer- 
web of first primary is entire, but that of the second, tiiird and fourth webs 
is scalloped. The tip consists of four feathers, the fifth being much shorter 
than the first, which is exceeded in length by the fourth. The third primary 
is the longest, while the second is longer than the fourth. 
The tail is long, about tv/o-tliirds the length of the wing, and is rounded 
in shape, the feathers broad and ten in number. 
The legs are very small, the tarsus entirely feathered : the toes are short 
and covered with scuteUate scales : the fore toes are joined at their bases with 
small webs, the hind toe free. The outer and inner are subequal, but much 
shorter than the middle toe. The claws on all the toes except the middle 
one are very small : the claw of the middle toe is long with the inner edge 
expanding and serrated. The number of phalanges in the outer toe are four 
orJy. 
The above description is compiled from Caprimulgus macrurus Horsfield, 
which is here generically separated from Caprimulgus as I find it differs in an 
essential feature, viz., the wing-structure. In C. europceus the tip of the wing 
consists of three feathers onty, the fourth being much shorter. The second 
primary is longest, but little exceeds the first which is slightly longer than the 
third. In addition the plumage of C. europceus is much harsher, and the tail 
is less rounded and shorter in proportion. 
In this order the birds are superficially so alike that it becomes difficult 
to distinguish them by external features. In the present instance the wing- 
formation is a striking item and can justly be deemed of generic import. I, 
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