PASSERES MESOMYODI OR CLAMATORES. 509 



turned out in this country, \Ahore it niiiy become naturalized, as it seems to lie already estab- 

 lished in some localities on Long Island, N. Y. The closely related Kamtschatkau Sky- 

 lark {A. blakistoni) may occur in Alaska. 



Suborder PASSERES MESOMYODI, OR CLAMATORES : 

 Non-melodious or Soxoless Passeres. 



Mesomyodian scutelliplantar Passeres tvith ten fully developed primaries. — Syrinx with 

 fewer than four distinct pairs of intrinsic muscles, iuserted at middle of upper bronchial half- 

 rings, representing the mesomyodian type of voice-organ, and constituting an uncomplicated 

 and ineffective musical apparatus. (The word mesomyodian is from the Gr. fiecros, mesos, mid- 

 dle, and iJLvd)8r]s, muodes, muscular, referring to such insertion of the syringeal muscles into 

 the middle of the upper bronchial cartilages, not at their ends as in Oscines or Acromyodi ; Gr. 

 aKpos, akros, at the tip or end, apical.) Side and back of tarsus, as well as the front, covered 

 with variously arranged scutella, so that there is no sharp undivided ridge beliiud (as, e. g. in 

 lig. 344, a). Ten fully developed primaries, the 1st of which, if not equalling or exceeding the 

 2d, is at least two-thirds as long. (See p. 246, where the Oscines are defined as acromyodian 

 laminiplantar Passeres with 9 fully-developed primaries, or 10 and the 1st short or spurious.) 



In most Mesomyodi or Clamatores, the lower end of the trachea itself, aside froiri its nniscles, 

 undergoes no further modification fnmi an ordinary Passerine type; and the birds which are 

 thus not further affected in their windpipes form a group called Oligomyodce (Gr. oA/yoy, oUgos, 

 few, as the syringeal muscles are). All our mesomyodian birds are also oligomyodian ; there 

 are also several extralimital families, as the OxyrhamphidcB, Pipridce, and Phytotomidte of 

 Neotropical America, and the Old World Philepittidce. Pittidce, Xenicidce, and Eurylcemidce. 

 Again, some mesomyodian birds exhibit a further modification of the same organ, which affects 

 the structure of the lower end of the trachea itself; and such are called Tracheophonce. These 

 tracheophonous birds are all Neotropical ; they form the four families, Dendrocolaptid(V, Formi- 

 cariidiB, Conopophagidce, and Pteroptochida: 



The essential character of Passeres Mesomyodi or Clamatores, as distinguished froui Pas- 

 seres Acromyodi or Oscines, is thus seen to be an anatomical one, consisting in non-development 

 of a singing apparatus; the vocal muscles of the lower larynx (syrinx) being small and few, 

 or else forming simply a fleshy mass, not separated into particular muscles ; in either case in- 

 serted in a special manner into the bronchial half-rings ; in the case of oligomyodian forms 

 without further modificatiim of the trachea itself, such as occurs in tracheophonous forms. 

 This character, though subject to some difficulty of determination, corresponds well with the 

 principal external character assignable to the whole suborder, — namely, a certain condition 

 of the tarsal envelop rarely if ever seen in higher Passeres. If tlie leg of a Kingbird, for ex- 

 ample, be closely examined, it will be seen covered with a row of scutella forming cylindrical 

 plate.s continuously enveloping the tarsus like a segmented scroll, and showing on its postero- 

 internal face a deep groove where the edges of the envelop come together; this groove widen- 

 ing into a naked space above, partially filled in behind with a row of small plates. Such a 

 tarsus is called exaspideun (Gr. e'^, e.r, outside, and aanis, aspis, a shield, scute, plate) ; it 

 characterizes the whole family Tyrannidcc. When the arrangement of the scndls is reversed, 

 so that they lap round the inner side of the tarsus, it is called endaspidean (Gr. eVSo-, endo-, 

 within, inside): it is shown by the South American Dendrocolaptidtc, for example. When the 

 whole back side of the tarsus is broken up into many little dose-set scutella, the forniation is 

 termed pycnaspidean (Gr. ttvkvos, jmknos, ch)se, firm, compact); Cotingidfe show this feature. 

 In some rare cases, as Philepittidrc, the plantar laminae are rectangular, in regular series, giving 

 the taxaspidean arrangement (Gr. rd^ts, taxis, a rank or row). As a rare anomaly in this sub- 

 order, Pittid(B and Xenicidre have ochreate or booted tarsi, as if tln-y l»elonged to the highe.^t 



