INTRODUCTION iij 



Lastly we arrive at the Passeres, and here, as already mentioned, the 

 researches of Garrod and Forbes prove to be of immense service. It was 

 of course not to be supposed that they had exhausted the subject even as 

 regards their Mesomyodi, while their Acromyodi were left almost untouched 

 so far as concerns details of arrangement ; but later investigations have 

 produced a much more manageable scheme, and so far as it is goes Dr. 

 Gadow seems to have good reason for the groups he has made, even though 

 exception be taken to part of his nomenclature. 



Thus we reach the true Oscines, the last and highest group of Birds, 

 and one which, as before hinted, it is very hard to subdivide. Some two 

 or three natural, because well-differentiated. Families are to be found in 

 it — such, for instance, as the Hirundinidse (Swallow), which have no 

 near relations ; the A Imididx (Lark), that can be unfailingly distinguished 

 at a glance by their scutellated planta, as has been before mentioned ; or 

 the Meliphagidse (Honey-eater), with their curiously constructed tongue. 

 But the great mass, comprehending incomparably the greatest number of 

 genera and species of Birds, defies any sure means of separation. Here 

 and there a good many individual genera may be picked out capable of 

 the most accurate definition ; but genera like these are in the minority, 

 and most of the remainder present several apparent alliances, from which 

 we are at a loss to choose that which is nearest. Four of the six groups 

 of Mr. Sclater's " Laminiplantar " Oscines seem to pass almost imperceptibly 

 into one another. We may take examples in which what we may call the 

 Thrush-form, the Tree-creeper-form, the Finch-form, or the Crow-form is 

 pushed to the most extreme point of differentiation, but we shall find that 

 between the outposts thus established there exists 'a regular chain of 

 intermediate stations so intimately connected that no precise lines of 

 demarcation can be drawn cutting off one from the other. 



Still one thing is possible. Hard though it be to find definitions for 

 the several groups of Oscines, whether we make them more or fewer, it is 

 by no means so hard, if we go the right way to work, to determine which 

 of them is the highest, and, possibly, which of them is the lowest. It has 

 already been shewn (page 73) how, by a woeful want of the logical appre- 

 hension of facts, the Turdidx came to be accounted the highest, and the 

 position accorded to them has been generally acquiesced in by those who 

 have followed in the footsteps of Keyserling and Blasius, of Prof. Cabanis 

 and of Sundevall. Now the order thus prescribed seems to be almost the 

 very reverse of that which the doctrine of Evolution requires, and, so far 

 from the Turdidae being at the head of the Oscines, they are among its 

 lower members. There is no doubt whatever as to the intimate relation- 

 ship of the Thrushes {Turdidae) to the Chats (Saxicolinse), for that is 

 admitted by nearly every systematizer. Now most authorities on classifica- 

 tion are agreed in associating with the latter group the Birds of the 

 Australian genus Petroeca and its allies (Wheatear, pp. 1035, 1036) — 

 the so-called " Robins " of the English-speaking part of the great southern 

 communities. But it so happens that, from the inferior type of the osteo- 

 logical characters of this very group of Birds, the late Prof. Parker called 

 them (2Va?is. Zool. Soc. v. p. 152) " Struthious Warblers." Now if the 

 Petrceca-gron-p be, as most allow, allied to the Saxicolinie, they must also 



