TIIK RIBS IQ^ 



rnicl diminish very sradually. Not raivl^- the tirst coeeyKcaJ v.-rtrhra unit.'s with 

 the sacrum. 



Vertebral Curves.— The cervieal region is praetieall\- straight. The th(jraeic 

 and Imnhar r.^gions form a gentle cmrve, concave ventrall\', the highest point of 

 whi.-h IS at the junction of the t\v., regions. The sarral promontory is not so pro- 

 nounced as m tlie ox, and tlie sacral curve is flatter. 



Fig. 17.J. — Sacru_m axd First Coccygeal Vertebka of Fig. 171. — SAcitim -vxd First Cuccygeal "N'ertehka of 



,Pig; Dorsal View. Pig; \kxtr\i. View. 



I-IV. Ardiri of >arrLi! ViTO-bra; 1,2, .3, dursal sacral I~IV, Sacral vcrtrhra^ (tjn.lico: 1, 1', :i, ventral .-acral 



foramina; 4, sinnlar Inranicn lictween sacrum ami first foramina; 4, similar for'anicn lid ween saiaaim ami tirst 



CDC^■\-^eal A-crt'4ira; .1, I.hkj\- uf first s;itTal vcrtclira; B, coi;c\-;^c;iI \-crIcl)ra; .l.l.mly of first sticral ^-crtcllla; B, 



articular proc,--; f\ w intr; D. auricular .surface; E, articu- artitailar process; C, wing; D, atuTcular surface; L', first 



lar processes; F, first coccygeal vertebra. cijcc_\'geal vertebra. 



Length. — The regional length.s of the vertebral column of :t large Berkshire .sow wore as fol- 

 lows: Cervical, 24 cm.; thoracic, .53. .5 cm.; lumbar, 31 cm.; .stici'tt), 17 cm.; coccygctti, ;-i5 cni. 



Variations. — The occurrence of fifteen thoracic vii'tcbrtt' is (|uiti' coiniuoii, attd Ihc exislciice 

 of sixteen or even seventeen has been recorded. Kciltiction to thiftcen is \-i'fv ftifc. ,Six ttml 

 seven kimbar vertebrse seem to occur with about cqutil frequency, and rtYluction to hve is on rec- 

 ord. The number of coccygeal vertebnc varies from twenty to twenty-six trccording to the records 

 of several observers. Lesbre states that he has found tv\'eQty-three most frefiuentlj'. 



THE RIBS 



The ribs number foiu'teen or fifteen pairs, of which se\'en art^ st(>rnal and seven 

 or eight asternal usually. They are in general strongly curvetl in the improved 

 breeds, so that there is a fairly distinct angle, except toward the end of the series. 



