INTRODUCTION g? 



that, disencumbered from both the last two, is eminently natural, and 

 easily dealt with. A great break then occurs, and the new series is 

 opened by the Eleventh " Order," Cohimbse, with 3 Families, Carpophagidse, 

 Columhidse and Gouridse, " or perhaps a fourth," Didunculidse} — the Dodos 

 being "held to belong to quite a separate section of the order." The 

 Twelfth "Order" is formed by the Pterocletes [!] (Sand-Grouse); and 

 then we have tlie very natural group Gallinse, ranking as the Thirteenth. 

 The next two are the Opisthocorni and Hemipodii for the Hoactzin and 

 the Twnicidse, (Hemipode) respectively, to which follow as Sixteenth and 

 Seventeenth the Fidicarise and Alectorides — the former consisting of the 

 Families Rallidae (Rail) and Heliornithidae, (Finfoot), and the latter of 

 what seems to be a very heterogeneous compound of 6 Families — Aramidse, 

 (Limpkin), Eurypiigidx (Sun-Bittern), Gruidse. (Crane), Psophiidx (Trum- 

 peter), Gariamidx (Seriema) and Otididse ^ (Bustard). It is confessedly 

 very puzzling to know how these varied types, or some of them at least, 

 should be classed ; but the need for the establishment of this group, and 

 especially the insertion in it of certain forms, is not explained by the 

 author. Then we have " Orders " Eighteen and Nineteen, the Limicolee, 

 with 6 Families, and Gavise, consisting only of Laridse, (Gull), which 

 taken in their simplest condition do not present much difficulty. The 

 last are followed by Tuhinares (Petrels), and these by Pygopodes, to 

 which only 2 Families Golymhidx (Diver) and Alcidse (Auk) are allowed — 

 the Grebes being included in the former. The Inipennes (Penguin) form 

 the Twenty-second, and Crypturi (Tinamou) complete the Carinate Sub- 

 class. For the Eatitx only three "Orders" are allotted — Apteryges, 

 Casuarii and Struthiones. 



As a whole it is impossible not to speak well of the scheme thus 

 sketched out, so far as materials for it existed ; and, in 1884, an attempt 

 was made {Encycl. Brit. ed. 9, xviii. j)p. 43-49) to indicate those points 

 in recent Classifications which then seemed to have been established on a 

 pretty sure footing, though therein the writer had no intention, any more 

 than he now has, of inventing (as has sometimes been supposed) a new 

 arrangement of Birds. He did, however, try to shew that some positions 

 which had been taken up could not be maintained, and among other things 

 that the " Subclass " Odontornithes, founded as above mentioned (page 87) by 

 Prof. Marsh, was artificial, for, while Birds yet retained the teeth they 

 had inherited from their Reptilian ancestors, two remarkable and, in the 

 opinion of many, distinct groups of the Class had already made their 

 appearance, which two groups persist at the present day in the Aves 

 Ratitse and Aves Carinatse long ago recognized by Merrem. Furthermore, 

 while the Ratite type (Hesperornis) presents the kind of teeth which 

 indicate (in Reptiles at least) a low morphological rank, the Carinate 

 type (Ichthyornis) is furnished with teeth set in sockets and shewing a 

 higher development. On the other hand this early Carinate type has 

 vertebrse whose comparatively simple, biconcave form is equally evidence 

 of a rank unquestionably low; but the saddle -shaped vertebrae of the 



^ In the eighth edition of the List of Vertehrated Aniinals in the Zoological 

 Gardens, which, being published in 1883, may be taken as expressing Mr. Sclater's 

 later views, the first two Families only are recognized, the last two being placed 

 under ColumUdee. " Wrongly spelt Otidse. 



