PTILOGONATINAS. 409 
It may be considered that the presence or absence of scutelle . 
on the tarsus is a matter of comparatively slight importance, since 
in some Thrushes having normally smooth tarsi, we occasionally find 
individual specimens exhibiting scutelle, and the Mocking Birds 
differ from the true Thrushes in having such scutelle. Yet when 
to this we add the tendency in Ptilogonys and Phenopepla to 
division of the whole length of the lateral plates, and even occasional 
indications of a supplementary series on the posterior edge of tarsus, 
the difference from the smooth tarsi of MWyciadestes and its allies, is 
one of essential moment. Add to this the peculiarities of marking 
in young birds, and the difference of vocal powers, and the grounds 
for separation would seem well established, and the assignment of 
the Myiadestine, as a subfamily, to a place near the Saxicolidx and 
Turdide (perhaps better under the latter), well founded, as all the 
characters referred to above apply to the Turdine. Since, however, 
other authors may not agree with me in this view, and as the Jur- 
didx have already been discussed, I propose to present the Myia- 
destinz in the present .article after the Ptilogonatinx, and to leave 
the final decision of their true position to a future period. 
The comparative diagnoses of Myiadestine and Turdinz may be 
expressed as follows :— 
Common Cuaracters.—Tarsi without regular transverse scutelle, except at 
lower end. Wings acute, pointed, as long as or longer than tail, which is 
but slightly graduated. First primary rarely half 2d, which exceeds the 
secondaries. Base of quills buffy yellow, as are inner edges. Tail spotted 
or varied at the end. Young birds with many light spots. Very melodious 
singers. 
Myiadestine. Bill short, much depressed; mouth deeply cleft; width 
at base about equal to the distance from nostril to tip, or greater; 
commissure more than twice distance from nostrils to tip of bill, and 
nearly two and a half times length of gonys. Legs weak; tarsi 
rather longer than middle toe and claw. Tail feathers tapering 
slightly from base to near tip, giving a slightly cuneate appearance 
to the tail. 
Turdine. Bill stouter, more lengthened; narrow at base and more 
compressed ; width at base less than distance from nostril to tip; 
commissure not more than twice distance from nostrils to tip. of bill, 
and about twice length of gonys. ‘Tarsi stouter, longer than middle 
toe and claw. Tail feathers widening slightly from base to near tip, 
giving a parallel sided or slightly fan-shaped appearance to the tail. 
The Mimine differ from both in the strongly scutellate tarsi ; 
shorter, more rounded wings, the Ist primary generally half the 2d; 
the tail usually much graduated, ete. 
