26 CHIKANOSUKE OGAWA 



B III. Vesicle small and somewhat elongated in its sagittal axis. 

 The wall is thick ventromedially. Rotation is complete. 

 B IV. Vesicle too small to justify conclusion. 

 Examination 22 hours after operation. 



A I (fig. 6). The vesicle presents an oval shape in its mediolateral 

 axis. The lateral wall is thick, the medial wall thin. A large cell 

 group, probably the ganglion, is attached to the dorsal wall. No 

 rotation. 



A II. The vesicle appears oval in section with a slight vertical 

 elongation. The ventral wall is thickest, especially in its medial part. 

 Slightly caudal the ganglion is attached to the medial wall of the 

 vesicle. No significant difference is recognizable between the medial 

 and lateral wall. Rotation is complete. 



A III. Judged by its general form, this vesicle appears to have com- 

 pleted rotation, but a definite ciiterion is lacking. 



B I. The vesicle, oval in shape, is in its normal position. The 

 dorsal part indicates the formation of the endolymphatic appendage. 

 Rotation is complete. 



B II. Series incomplete. 



C I. Criteria lacking. 



C II. The vesicle is divided into two parts, an upper smaller part 

 and a lower larger one. The wall is thick ventrally. It is difficult 

 to draw any conclusion as to its position. 



Examination 24 hours after operation. 



A I. The form and thickness of the wall afford no clue as to the 

 position of the vesicle. 



A II. This vesicle is entirely normal and corresponds to the normal 

 side in every respect. Probably, through some mistake the original 

 vesicle was not removed. 



A III. Vesicle is oval. The wall is thick ventrally and in its lower 

 medial part. The ganglion is attached to the dorsomedial part. Rota- 

 tion is complete. 



B I. The vesicle is round. The wall is thin laterally and thick 

 medially. The ganglion is attached to the ventral wall. Rotation is 

 half completed. 



B II. Vesicle broken. 



B III. The vesicle is round in section. The medial wall is thick, 

 especially in the upper part. Rotation is half completed. 



C I. The vesicle is nearly round in section. The dorsomedial wall 

 is thick. Vesicle has rotated half-way. 



C II. Sections destroyed. 



C III. Vesicle too small for study. 



D I. No criterion could be found in this case. 



D II. No vesicle. 



D III (fig. 7). The vesicle is small and round. The wall is thin 

 laterally and distinctly thick ventromedially. Rotation is complete. 



E I (fig. 8). The vesicle is oval with the axis inchned laterally. A 

 part of the lateral wall is still open; this must be the original lateral 

 side. The skin has h(>ale<l thoroughl^^ Rotation complete. 



