240 SYSTEM A TIC SYNOPSIS. — PA SSEBES — OSCINES. 



In such cases there are also ten fully developed primaries, the first of which, if not equallijiig of 

 bt'iug itself the longest, is at least two-thirds as long. (See p. 428, fig. 279.) 



These combinations of characters may he contrasted for the purpose of dividing the great 

 group Passeres into two sections, conventionally denominated sub-orders. 



1. Suborder PASSERES ACROMYODI, OR OSCINES: Singing Birds. 



Syrinx with four or five distinct pairs of intrinsic muscles, inserted at the ends of the three 

 upper bronchial half-rings, representing the acromyodian type of voice-organ, and constituting 

 a highly complex and eflFective musical apparatus. Side of tarsus covered with a horny plate 

 meeting its fellow in a sharp ridge behind ; front of tarsus also sometimes laminate. Prima- 

 ries ten, with the first short or spurious, or apparently only nine. 



Here belong all the North American famUies of Passeres, with the single exception of the 

 Tyrannidce, or Flycatchers, which are clamatorial (mesomyodian). The only North American 

 exceptions to the diagnosis given are afibrded by the Alaudidce, or Larks, and certain Troglo- 

 dytidce, which, with an oscine syrinx and wing-structure, do not have a bilamiuate tarsus. Of 

 our 394 Passerine species, no fewer than 363 are Oscine. The name is the Lat. os'cen, in n. 

 pi. os'dnes, diviuing-birds — those whose notes were regarded as augural. 



It is a question, which one of the numerous Oscine families should be placed at the head 

 of the series. Largely, perhaps, thi'ough the influence of those ornithologists who hold that 

 fusion of the tarsal envelope into one continuous plate indicates the acme of bird-structure, the 

 place of honor has of late been usually assigned to the thrushes. But only a part of the 

 thrushes themselves show this character ; on which account, probably, the rest were associated 

 by Cabanis with the wrens. It seems to me most probable that this character, though unques- 

 tionably of high import, should be taken as of less value than the reduction of the number of 

 primaries from ten to nine ; and I am at present inclined to believe that eventually some Oscine 

 family with only nine primaries — as the finches or tanagers — will take the leading position. 

 Here, however, I follow usage in the sequence of the North American families of Oscines, as 

 follows : — Turdidce, ChamceidcB, Paridcc, Sittidce, Certhiidce, Troglodytidce, Alaudidce, Mota- 

 dllidcE, SylvicolidcE, Tanagridce, Hii-undinidce, Ampelidce, Vireonidce, Laniidce, Fringillidce, 

 Icteridae, Corvidee, Sturnidce. 



1. Family TURDID^ : Thrushes, etc. 



The essential character t)f this great gi'oup of 

 Oscines is, booted tarsi and ten primaries, the 1st 

 spurious. But such expression requires qualification, 

 for the Turdidce do not show this combination with- 

 out exception, and birds of some other families do 

 possess it. Though it be as natural as any other 

 Oscine family of equal extent and variety, and equally 

 close relationships with other groups, it is in the 

 nature of the case insusceptible of perfect definition 

 in concise terms. The North American representa- 

 tives, however, may readily be circumscribed in a man- 

 ner enabling the student to assure himself of the family 

 to which they belong. Besides the true Thrushes, the 



_ , ^ ^ ^_, family as at present constituted includes the Mocking 



Fig. 113. — Thrushes: European Redwing ^^ \ J;. t,i i.- j t^- i ^ ^ n T 



{Tardus iliacus) and Fieldfare (T. pilaris). Thrushes, Dippers, Blue-birds, Kinglets and b^nat- 



From Dixon. catchers, with stray representatives of certain Old 



World forms, the Chats and Sylvines, sometimes held to represent separate families (Sazico- 



