PROFESSOR OWEN ON THE MEGATHERIUM. 
729 
and connections throughout the lumbar series, where it is above and distinct from 
the diapophyses, which are serial repetitions of the base supporting the anchylosed 
ribs on the first lumbar vertebra. 
Order Carnivora. 
In the Lion {Fells Leo), with dl3, 17, the common base of the met- and an-apo- 
physes appears as a strong ridge above the diapophysis of the tenth dorsal ; the ridge 
increases in the eleventh, divides into a large and strong metapophysis and anapo- 
physis in the twelfth ; both of these increase in size in the thirteenth dorsal. The 
metapophyses are continued throughout the lumbar region ; the anapophyses dimi- 
nish to short and thin styliform processes, underlappkig the prozygapophyses of the 
first four lumbars, and becoming rudimental in the rest. The prozygapophyses are 
distinctly developed in all the dorsal vertebrae anterior to that in which the metapo- 
physes are superadded to them. 
In the Puma (Fells concolor), with the same vertebral formula, the common ac- 
cessory tubercle indicates the anapophysis by its backward production from above 
the diapophysis of the ninth dorsal (Plate XLV. figs. 5 and 6, a) : the anapophysis 
grows longer in the tenth (fig. 5, a) ; and in the eleventh the metapophysis (m) sud- 
denly shoots upwards and forwards, the anapophysis (a) diverges from it backwards, 
underlapping the metapophysis of the next vertebra, and both processes far surpass 
the diapophysis (d) in size, which clearly, however, coexists with them. It disap- 
pears in the thirteenth vertebra, in which both ana- and met-apophyses have in- 
creased in length ; and the only question that remains with regard to the ‘ trans- 
verse process ’ (d) of the following vertebrae is, whether it includes the diapophysis 
at its base, or consists solely of the connate pleurapophysis. The eleventh vertebra 
permits of no doubt as to the distinctness of the diapophysis (d) from the two larger 
superadded processes (m and a), and, in fact, a rudiment of the diapophysis may 
be recognized above the costal pit in the last dorsal. Fig. 6 shows the prozygapo- 
physes (z) existing, as in all the anterior dorsals, independently of the metapophyses*: 
fig. 7 shows them coexisting (z) with metapophysis (m), anapophysis (a), and diapo- 
physis (d). The neural spine in this vertebra, which is the centre of motion of the 
spine, is low and nearly vertical ; the longer spines of contiguous vertebrae converge 
to it. 
In the Hyoena crocuta, with c? 15, / 5, the anapophyses begin to be distinct, and to 
project backwards in the thirteenth dorsal, underlap the prozygapophyses in the first 
three lumbar, and subside on the penultimate lumbar vertebra. 
In the Wolf (Cams Lupus) and Dog, with d 13, / 7, the metapophyses begin to be 
developed on the eighth dorsal, and are continued throughout the lumbar series : the 
anapophysis projects backwards in the eleventh dorsal, and subsides to a mere ridge 
in the penultimate lumbar. In the Fox they begin to be developed on the seventh 
* ‘ Apophyses antoMiques,’ Straus-Dueckheim. 
