64 DICTIONARY OF BIRDS 



as the highest problem of the systematist, but rather their correct limita- 

 tion. Again the arrangement followed in the Pterylographie was of 

 course based on pterylographical considerations, and we have its author's 

 own word for it that he was persuaded that the limitation of natural 

 groups could only be attained by the most assiduous research into the 

 species of which they are composed from every point of view. The com- 

 bination of these three facts will of itself explain some defects, or even 

 retrogressions, observable in Nitzsch's later systematic work when com- 

 pared with that which he had formerly done. On the other hand some 

 manifest improvements are introduced, and the abundance of details into 

 which he enters in his Ptenjlograjjhie renders it far more instructive and 

 valuable than the older performance. As an abstract of that has already 

 been given, it may be sufficient here to point out the chief changes made 

 in his newer arrangement. To begin with, the three great sections of 

 Aerial, Terrestrial and Aquatic Birds are abolished. The " Accipitres " 

 are divided into two groups, Diurnal and Nocturnal ; but the first of these 

 divisions is separated into three sections : — (1) the Vultures of the New 

 World, (2) those of the Old World and (3) the genus Falco of Linnseus. 

 The " Passerinse," that is to say, the true Passer es, are split into eight 

 Families, not wholly with judgment ; ^ but of their taxonomy more 

 is to be said presently. Then a new Order "Picarix" is instituted 

 for the reception of the Macrochires, Cuculinae, Picinx, Psittacinas 

 and Aviphibolse of his old arrangement, to which are added three ^ 

 others — Gaprimulgiiise, Todidae, and Lipoglossae — the last consisting of the 

 genera Buceros, Upupa and Alcedo. The association of Alcedo with the 

 other two is no doubt a misplacement, but the alliance of Buceros to 

 Upupa, already suggested by Gould and Blyth in 1838 ^ (Mag. Nat. Hist. 

 ser. 2, ii. pp. 422 and 589), though at first sight unnatural, has been 

 corroborated by many later systematizers ; and taken as a whole the 

 establishment of the Picariee was certainly a commendable proceeding. 

 For the rest there is only one considerable change, and that forms the 

 greatest blot on the whole scheme. Instead of the Ratitx of Merrem 

 being recognized as before as a Subclass, they were now reduced to the 

 rank of an Order under the name " Platysternss" and placed between the 

 " Gallinacex " and " Grallx," though it was admitted that in their pterylosis 

 they differ from all other Birds, in ways that the author is at great pains 



^ A short essay by Nitzsch on tlie general structure of the Passerines, wiitten, it is 

 said, in 1836, was published in 1862 [Zeitschr. Ges. Naturwissensch. xix. pp. 389- 

 408). It is probably to this essay that Burmeister refers in the Pterylographie (p. 

 102, note ; English translation, p. 72, note) as forming the basis of the article 

 " Passerinse " which he contributed to Ersch and Gruber's Encyklopadie (sect. iii. 

 bd. xiii. pp. 139-144), and published before the PterylograpMe. 



- By the numbers prefixed it would look as if there should be four new members 

 of this Order ; but that seems to be due rather to a slip of the pen or to a printer's 

 error. 



■^ This association is one of the most remarkable in the whole series of Blyth 's 

 remarkable papers on classification in the volume cited above. He states that Gould 

 suspected the alliance of these two forms " from external structure and habits alone ; " 

 otherwise one might suppose that he had obtained an intimation to that effect on one 

 of his Continental journeys. Blyth "arrived at the same conclusion, however, by a 

 difi'erent train of investigation," and this is beyond doubt. 



