Osteology o/Aramus scolopaceus. 43 
the. three dorsal vertebrae which is precisely like that in the 
last-mentioned species : the vertebrae are united ventrally 
but not dorsally. In Baleai'ica we again find an approxima- 
tion towards the conditions observable in Aramus. Three 
dorsal vertebrae, which are_, as in the other types, the first, 
second, and third of the series, are completely fused below ; 
it is true that the fusion above is by no means so complete 
^^ 'in. Aramus, but there are considerable bridges of bony 
matter uniting the spinous processes. The difference in these 
points between Aramus and Balearica is indeed not nearly 
so great as between either of these genera and Grus or 
Tetrapteryx. Aramus is only a short stage in front of 
Balearica ; and both genera, it will be observed, must be 
regarded as comparatively specialized Cranes, since it cannot 
be doubted that the primitive arrangement is for the vertebrae 
to be separate and not fused at all. Such a point of resem- 
blance, however, clearly need not be considered as one of 
affinity ; no (me can doubt that a more complete fusion 
between certain vertebrae is a specialization which might 
readily have been acquired several times independently. 
With regard to this fusion between separate vertebrae of 
the dorsal series, I may observe that Psophia shews an advance 
upon Aramus and Balearica : in the former genus the fusion 
is so complete that even the intervertebral nerve-foramina 
are almost obliterated ; those of Aramus are not nearly so 
much so. 
There are some further minutiae of structure of the last 
cervical and the first dorsal vertebrae upon which it is 
requisite to insist, inasmuch as they offer points for dis- 
criminating Aramus from its allies among the Cranes. 
In this genus the last two cervicals have, as has been 
stated, a single median hypapophysis. In addition to this 
process, which is strongly developed, there are two small 
lateral hypapophyses, one on either side of the median 
downgrowth ; these two processes approach a little nearer 
to the ventral median line on the last than on the penulti- 
mate cervical vertebra. The first dorsal vertebra of Aramus 
is marked off from the cervicals by the fact that the two 
lateral processes cease to arise independently from the 
