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composed of three quills of which the distal one is the longest, and 
the proximal one the shortest. The pollex shows no indication of 
a horny nail. The rec trices are twelve in number ; they are all 
soft and very short ; the central pair is the longest, the others 
shorten gradually towards the outside. The Turnices have like- 
wise twelve rectrices, while in most of the Ra sores the number 
is increased. 
The dorsal feather tract is interrupted by a long spinal apterium 
which begins on a level with the shoulder-joint and is continued a 
little beyond the level of the hipjoint. Each half of the tract is 
composed of three to seven rows of feathers of which those nearest 
the middle line are the strongest. Behind the spinal apterium 
the tract is continued on to the oil-gland. The humero-scapular 
tract is very broad, its feathers are longer than the cubitals and 
form a conspicuous parapteron. This humeral tract is connected 
through sparingly developed feathers on to the ventral middle 
cervical tract, but not at all with the dorsal cervical tract, which 
latter occupies the whole dorsal surface of the neck. The femoral 
tract is isolated and very distinct ; its feathers are so long that 
they form the chief covering of the outer surface of the fleshy 
part of the leg. The feather tracts on the under surface : — the 
under surface of the neck is covered uniformly, then the tract 
divides, leaving a bare interclavicular space. Each tract divides 
again on a level with the anterior end of the keel, into a lateral 
thick patch which extends over the lateral part of the sternum, 
over the sternal ribs, and into a narrower branch which runs 
nearer the middle line, where it swells out on the abdomen and 
then narrows again, being continued by scattered feathers towards 
the hinder end of the os pubis. The whole distribution and shape 
of the feather tracts closely resemble that of the Turnices. 
The aftershaft is present, very thin and delicate, but much 
longer than in the Rasores. The oil-gland is large and tufted, it 
is otherwise naked except on the dorsal middle line on which the 
spinal tract is continued. The nostrils are formed by very long 
and wide slits ; they are protected by a large, soft upper valve, 
which internally is composed of a cartilaginous thin plate. The 
whole operculum is quite bare of feathers. The sheath of the bill 
is composed of one piece only. The tarso-metatarsus is covered 
in front with one row of about twelve or more transverse scutes, 
which reach over to the median and outer side. The posterior or 
plantar surface is protected by a similar row of transverse scutes. 
The narrow space between the dorsal and ventral row of scutes is 
filled by one row of small granular scales on the outer side, by two 
rows on the median side. The same covering of small granular 
scales exists on the distal half of the bare portion of the leg. The 
plantar side of the whole heel is covered with numerous narrow 
transverse scutes ; the outer and median spaces are filled up by 
small granular scales. The number of toes is four, the hallux 
