1866.] PROF. W. LILI.JEBORG ON THE CLASS OF BIROS. 13 



the first row on the lower arm do not extend beyond the middle of 

 the cubital quills, and we meet with only one row of greater upper 

 wing-coverts. As far as known, only one carotis communis, or 

 truncus caroticus impar, which arises from the left arteria subclavia. 

 Lively and active birds, with a fast and excellent flight, which move 

 easily as well on the ground as on the branches of the trees. They 

 generally jump on the ground, and seldom run. Some of them 

 have a separate muscular apparatus for singing in the larynx inferior 

 and a more or less exquisite song. Doubly monogamous. Altrices. 

 Note. — This order embraces the typical forms of the group In- 

 sessores, and the birds that generally have the highest degree of 

 development. 



In the following tables I have tried to use the most important as 

 well as the most positive and evident characters, but have in this, 

 like others, met with much difficulty of finding such for the smaller 

 groups, or families and genera, in the higher orders. A great many 

 of the characters used are taken from Sundevall ; and in the Passeres 

 several from Cabauis. Their validity has first been fully tested. In 

 consequence of the above-mentioned difficulty we find that the place 

 in the system of a form in question cannot always be ascertained 

 from similar tables, as a more minute description is often necessary. 

 It must not, therefore, be expected that these tables should give an 

 infallible ground for the determination of the forms belonging to the 

 respective families and subfamilies, but only that they should denote 

 some of the most important characters that form the basis for the 

 groups, and give an easy review of these groups. Such a table shows 

 us most plainly what characters are common and what are not. 



As a great many of the exotic generic forms are not well known 

 to me, I do not insist that they can be all arranged under the 69 

 families and 144 subfamilies here characterized, and that the arrange- 

 ment of other families or subfamilies is unnecessary ; but I believe 

 that a great part of the genera have been considered. I may 

 mention that the difficulties arising in limiting the families Corvidce, 

 Paridce, and Sylvidce among the Passeres have induced me to make 

 these families more comprehensive than they have been. 



It seems that the Epimachini and Paradiseini should together 

 form a separate family ; but I have not been able to find any distin- 

 guishing characters, common to both, that make them distinct from 

 the Corvidce. The family Corvidce corresponds with " cohors Cor- 

 viformes," of Sundevall (Svenska Foglarna). The Troglodytini in- 

 clude forms of both Troylodytince and Timalince, Cabanis, excepting 

 some with emarginated bill. The other Liotrichidce, Cabanis, are 

 given to the Sylvidce, partly to Lanini and partly to Sylvini. It 

 seems that the family Brachijpodidce as arranged by Cabanis should 

 at least partly be included in the last-mentioned subfamily {Sylvini), 

 which, as it also embraces the Sylviadce, Cabauis, is very rich, and 

 contains about 500 species or more. I even include the Vireonince, 

 Cabanis, in the Sylvicolini. 



