TURDIDZ — TURDINZ: THRUSHES. 241 
lide and Sylviide), between which and Turdide, however, no line whatever can be drawn. 
The vast asseinblage of Old World Warblers are in fact much more thoroughly Thrush-like 
than are our Miminea, for example; and the Turdide would be much more homogeneous and 
easy to characterize if the Mock-birds and Gnat-catchers, with scutellate tarsi and not strictly 
spurious lst primary, were to be excluded. The relationships of the Mimine with the Wrens 
are really so close, that they have often been associated with the Troglodytide, to which they 
would probably be best assigned after all. The position of Polioptila is uncertain; but it 
cannot well go with Paride, and does not seem to be very different from some of the Sylvine 
forms now brought under Turdide. 
The North American embers of the Turdide offer collectively the following characters : — 
Wing of ten primaries, of which the lst is spurious or quite short — attaining functional 
size only in Mimine and Polioptiline. Wing more or less elongate and pointed, longer than 
the tail (shorter and more rounded in Polioptila and most Mimine). Inner secondaries never 
long and flowing as in Motacillide. Bill never stout and conical, nor with angulated commis- 
sure, nor flattened with gape reaching under the eyes; usually slender, straight or little curved, 
more or less compressed, subulate and acute, usually notched at end of upper mandible (but 
the nick frequently 
obsolete, and whole 
bill attaining ex- 
traordinary charac- 
ters in Harporhyn- 
chus). Nostrils oval 
or roundish, rarely 
linear, expdsed in 
conspicuous nasal 
fossee ; nearly or 
quite reached or 
overreached by the a 
frontal feathers, but 
never concealed by 
a dense ruff as in 
Parid, d Sittid Fig. 114. — Skulls of Turdide and Sylvicolide, nat. size; after Shufeldt. A, Oro- 
GOP BNC DUE: scoptes montanus; B, Sialia mexicana; ©, Cinclus mexicanus; D, Siurus nevius. 
Rictus bristled or Observe likeness between A and B, at points marked c, c’, l, /’; and between C and D, 
with bristl e-tippe d at points marked 8, b,/ d, d/. 
feathers, except in Cinclus. Tarsus normally booted, the anterior scutella, excepting a few 
below, being fused in a continuous plate, — not so in Mimine and Polioptiline. On the sides 
and behind, tarsus strictly laminiplantar (compare Alaudide and some Troglodyide). Tarsus 
usually also long and slender; never decidedly shorter than the middle toe and claw, often 
decidedly longer. Anterior toes deeply cleft, the inner to its very base, the outer adherent to 
the middle for only the length of its basal joint (compare Troglodytide). Hind claw never 
lengthened and straightehed as usual in Motacillide. ‘Tail feathers twelve; tail normally 
much shorter than the wings, sometimes about equal, only decidedly longer in some Mimine ; 
never cuneate, nor deeply forked, nor doubly rounded. 
Any North American bird showing booted tarsi, ten primaries, the 1st spurious, — and 
not double-rounded tail—is one of the Turdide. The group thus constituted is divisible 
‘ into several sub-families, which may be analyzed as follows with reference to the North Amer- 
ican genera : — 
ANALYSIS OF SUBFAMILIES. 
Turvinz: Typical Thrushes. Tarsi booted. Rictus bristly. Nostrils oval, exposed. 
Bill straight, shorter than head. First quill strictly spurious; 2d between 4th and 6th. Tail 
16 
