1905 | ANATOMY OF THE FERRET-BADGER. 29 
arteries and afterwards divide into right and left halves. The 
first pair of intercostals corresponds to the first branch of the 
Azygos*, The first six pairs of intercostals lie entirely to the 
left of the Azygos; the 7th artery on the right side and those 
which follow le to the right side of the Azygos. This point, I 
take it, is where originally the now missing right aortic arch 
joined the left aortic arch. In this region the aorta also gives 
off a number of fine slender branches to the cesophagus and to 
the lungs. The first of these branches arises a little way down 
the first right intercostal and supplies the windpipe; from or in 
the immediate neighbourhood of the next four right intercostals 
‘arise twigs for cesophagus and lungs; then follows a gap of two 
intercostals, the last twigs arising thon the 8th right intercostal. 
From the last intercostal in front of the diaphragm arises a 
diaphragmatic artery on each side; another diaphragmatic artery 
springs directly from the aorta behind the diaphragm, and 
independently of an immediately following suprarenal artery. 
I have carefully and, I hope, exactly compared the pre- 
diaphragmatic arteries of Helictis with those of its ally Galictis 
and with those of the Afluroid Swricata. 
The former, as might be expected, shows greater resemblances to 
FHlelictis than does the latter. There are, however, also difterences. 
There are 10 instead of 11 pairs of intercostals in front of the 
diaphragm, or, to be more absolutely accurate, 10 on one side and 
9 on the other; for the first intercostal has not a fellow and 
belongs to the left side. The fifth right intercostal is the first 
which passes to the outside of the Azygos vein. The pulmonary 
and esophageal branches arise in every case from the right 
intercostal vessels, and I counted four of them which have the 
following position: the first three arise from the first three 
right intercostals; the fourth springs from the fifth right 
intercostal. 
In Suricata tetradactyla there are 12 intercostals on the right 
side in front of the diaphragm and two additional ones on the 
left side. The most important pulmonary and cesophageal arteries 
arise separately from the aorta, though some spring “from right 
intercostals. The 8th right intercostal is the first which passes 
over the Azygos vein. 
* This vessel, as in most mammals, is present only on the right side. 
