The mouth is large and the oral cavity is gray or black. 

 There is no boundary between the oral cavity and the throato 

 The esophagus is rather long -with thick muscular walls and 

 it is clearly marked off from the stomacho 



Figure lo —Dissection of a tuna (abridged from Kishinouye 

 lo kidneys 2o intermuscular bones, 3o lower 

 branch of subcutaneous blood vessel j, 4o upper 

 branch of subcutaneous blood vessel, 5, liver, 

 60 pyloric caacas 7c air bladders 8" stomach, 

 9o spleenj, 10„ cloaca, lie. anuso 



Figure 2o --Outward appearance of livers 



Left to rights black tuna, big-eyed tuna, 

 yellowf in 



The stomach is extraordinarily long and is conical in 

 shape, reaching to abo-ve the anuSo The pyloric orifice opens 

 near the cardiac orifice on the left side of the stomach. 

 The walls are thick and tough with conspicuous longitudinal 

 folds, 30 - 40 in numbero Pyloric coeca are well developedo 

 Although the individual coeca are small, together they form 

 a Iso-ge masso Each coecum does not open individually into 

 the duodenum, but they open into 5-10 ducts of unequal 

 length which connect with the duodenum,, The intestine is 

 slender and fairly long and has three bendso The small 

 intestine and the rectum are both of roughly the same sizoo 



The liver is brown and covers the anterior part of the 

 ventral side of the stomach. It is divided into three 

 lobes of approximately equal size, and in the ^lack7 tuna 

 the surface has many small veins set closely togethero 

 Irregular branch lobes may be seen. In the big-eyed tuna a 

 small number of short venules appear only around the margins, 

 and in the yellowf in no venules appearc 



The gall bladder is a conspicuously elongated sac which 

 runs along the intestine on the inner side of the left lobe 

 of the liver. Its color is generally greenish. The spleen 

 is elongated in form and somewhat flattened, and it is 

 closely attached to the vicinity of the boundary between the 

 duodenum and the small intestine. 



^Translator's note s The figures in this paper, except for a 

 few graphs, have been omitted as they were too poorly 

 reproduced to copy. The captions have, however, been 

 retained to mark the locations of the figures in the original 

 text. 



10 



