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KAMAKICHI KISHINOUYE : 
The coeliaco-mesenteric artery (fig. Q) is a chief unpaired visceral artery 
originating just before the right pharyngeal muscle. The artery passes the 
right side of the muscle and is divided into three branches. I shall distinguish 
them as the first, second and third branch respectively ; numbering from the 
left dorsal side gradually to the right ventral side. The fate or destination of 
these branches are very different in different species, especially in the Plecostei. 
The first branch is short and simple, but the other branches are large and 
branching. In the Scombridae and Cybiidae the first branch nourishes the 
oesophagus and the left dorsal side of the stomach. The second branch is divided 
into two branchlets, one of which nourishes the right dorsal side of the stomach 
and the air-bladder, when it is present, and the other the spleen and intestine. 
The third branch the ventral side of the stomach and the pyloric coeca. In 
Thunnus the first branch is abortive, and nourishes the oesophagus only or is 
entirely absent. The second branch is divided into short parallel numerous 
arterioles in the right lobe of the liver and then reunited to about three branch- 
lets, one to the air-bladder, another to the right dorsal side of the stomach, 
and the remaining to the spleen, pyloric coeca, and intestine. The third branch 
raus along the abaxial side of the liver and is also divided into numerous 
arterioles in the middle and left lobes of the liver. These arterioles are reunited 
into principal canals, one nourishing the left dorsal side of the stomach, and 
the other the ventral side of the stomach, pyloric coeca, etc. In Thunnus orierdalis 
the third branch is subdivided into two before splitting into numerous arterioles. 
In Parathunnus the first branch nourishes the oesophagus and the left dorsal side 
of the stomach as in the Scombridae and Cybiidae. The second branch nourishes 
the air-bladder, right dorsal side of the stomach, spleen, and intestine ; v'hile 
the third branch is divided into two branchlets, one into the liver the other to 
the ventral side of the stomach, pyloric coeca, and intestine. In Neothunnus 
nearly the same as in Parathunnus, but the artery to the liver is much more 
degenerated. In Katsuioonus the first branch nourishes the oesophagus, left 
dorsal side of the stomach, but in Euthijnnus and Auxis it is very short, 
slender, and nourishes the oesophagus only. The second branch nourishes the 
right dorsal side of the stomach, spleen, and intestine, while the third branch 
nourishes the liver, ventral side of the stomach, and intestine. In the Katsu- 
wonidae the hepatic artery runs more or less forward near the root. 
