that connect the Orders and Families of Birds. 471 



niadcE as to confer the appellation of ^^ Piegrieches Hirondelles" 

 upon one of the groups of this family. It gives an equal insight 

 into the reasons why the Merulida and SturnidcB should have been 

 so closely united in the earlier systems, and some of their various 

 groups so frequently confounded together ; why, in particular, 

 Linnaeus should have placed in one and the same genus the Icteri, 

 that belong to the Sturnidce, and the Orioli, that come naturally 

 among the Thrushes; and why, again. Pastor and Lamprotornis 

 should so long have retained their station in the latter group. The 

 same consideration still further points out the cause of the simila- 

 rity between the Corvida and Psittacida in their relative perfec- 

 tion of form and structure ; and explains why the family of Psit- 

 tacidcc, though not the most perfect or typical with reference to its 

 own tribe, as it yields to the Picida in this point of pre-eminence, 

 is yet more perfect and typical than that family with reference to 

 the character of the order, in consequence of its analogy to the 

 Corvi. Many other similar coincidences and similar analogies 

 will suggest themselves to the reader here, as well as in the in- 

 ternal groups of the circles. 



There is another point of view in which the foregoing diagram 

 is of service to the inquiries of the ornithologist. It points out 

 the union of different groups with respect to characters not suffi- 

 ciently essential, or too artificial to form the basis of a natural 

 arrangement ; but which are yet important enough to force them- 

 selves upon our notice, and which have, in fact, formed in many 

 instances the foundation of well-received systems. On consult- 

 ing the above table, we shall perceive that the principles, which I 

 have endeavoured to illustrate, provide for due attention being 

 paid even to such minor characters by the juxta-position of the 

 groups in which they predominate ; and consequently, that the 

 mode of grouping which these principles dictate, combines every 

 advantage of artificial as well as of natural arrangement. Were 



we 



