SKELETON 849 
(b) Cervico-dorsal Vertebree, with movable ribs which do not 
reach the sternum. Their number may vary from 1 to 5, often 
individually and then in smaller limits. 
IL. Dorsal Veitebre begin at the first that is connected with the 
sternum by a pair of complete ribs, and end at the last that is not 
fused with the ILIUM. 
III. Pelvic Vertebre are all those that are fused with the iliac 
portion of the PELVIS, some of the anterior of them frequently 
bearing long and often complete and movable ribs, occasionally 
reaching the sternum. Hence it follows that “Thoracic” Vertebre, 
or those which are connected with the sternum, are not neces- 
sarily Dorsal Vertebrze, and therefore unless clear definitions are 
strictly adopted, a promiscuous application of those terms will lead 
to much confusion. This remark applies with still greater force to 
the terms ‘“dorso-lumbar” and “lumbar” Vertebra, which have 
a well-defined meaning in Mammals and in most Reptiles; but are 
absolutely inapplicable to Birds, as will presently be seen (page 855).! 
_ IV. Caudal Vertebrx, those following the last, and not connected 
with the ilium. 
A typical Bird’s vertebra consists of the centrum, an arch and 
two ribs. Roughly speaking, the arch encloses the spinal cord, and 
frequently extends dorsally into a spinous process, the size and 
position of which vary considerably in the different regions of the 
vertebral column. The arch also sends out a pair of anterior and 
a pair of posterior oblique processes (commonly called preezyga- 
pophyses and postzygapophyses), as well as a right and a left trans- 
verse process. The oblique processes terminate in facets, which 
articulate with those of the adjoining vertebra, so that the facets of 
the preezygapophyses look upwards and forwards and are overlapped 
by those of the postzygapophyses of the vertebra next in front. 
When the vertebre are free this rule is absolute, except in the case 
1 TABLE SHEWING THE NUMERICAL DIVERSITY OF THE SEVERAL 
VERTEBRAL REGIONS IN SOME FORMS OF BIRDs. 
3 } s ra 3 S 
ee lecaning ies meee gal ga ie 
sap eecl Biss Bi llsezsn his yes 
fe) om A a 6) ore 5 = 
Apteryx 4 ae elo bEAPANT SPs yae| ac! Treron olax. cs foals 2 3 3 
Dromeus - |20, 21] 2-4 5-7 5 Didide : plo 2 3 4 
Struthio 20 eres | a 5 Falconide . . {14 Doe 4scO Ose 
Anser cinereus 18 2 4 7, 8 || Striges : . | 14 Leezialico: 4,5 
Cygnus olor 23 2 4.9) 8 Psittaci a eS Le 23) aol oaG 
Sula 17 1 3 4,5 || Coceyges . o | LAso 23s ae bee aarG 
Ciconia 17 2 4,5 | 5 Cypselide . Bea ee Ay |e er 0 | ee) 
Phenicopterus 18,19} 2 a5 OG Caprimulgidw . |13,14} 1,2 | 3,4 | 4,5 
Larus . 15 2 5 6,7 || Trochili . 5, |e! 2 4 5 
Alea . S wel: 2 6-8 Gay, Buceros 6 sl: 2; 4 4,5 
Limicolz (most). | 15 2 5,6 | 6 Upupa. 5 . | 14 2 4 4,5 
Otish o: 5 16 2 5 5 Ricci. A Le 3 5 6 
Rallide 15 1 7,8 | 5-7 || Eurylemus. = ald 3 4,5 | 4 
Gallus . 16 2 4 4 Bittaye. A Bal ial) 3 AR Sreltce 
ge abe livia Lt 2 44 Passeres (most) . | 1 2, A 5 
54 
