246 PEors. J. n. SCOTT and t. j. paekee on a 



along its concave border. Seven of the nine (3rd to 9th) are snbglobular, the 10th is 

 more elongated. They are separated from one another by flat circular septa, each of 

 which is perforated, usually somewhat excentrically, by a nearly circular aperture, 

 about 2'5 cm. in diameter in the dried condition. 



The duodenum springs from one side of the last compartment, nearly midway 

 between its rounded blind end and the septum between it and the 9th chamber. Thus 

 the relation between the duodenum and stomach of Zipluus recalls that obtaining in 

 many animals between the ileum and colon. The mucous membrane of compartments 

 2 to 10 was soft and smooth. 



The intestine was 22-5 metres (74 ft.) long, and was uniformly circular in section, 

 showing no distinction between small and large intestine. Internally it was marked 

 with a network of ridges. The lymphatic glands of the mesentery were large and 

 nodular. 



5. Bespirafori/ Organs. 



The larynx is of the ordinary Cetacean character, and measures 21 cm. (S"25 in.) 

 from the posterior border of the cricoid to the tip of the arytenoid cartilages. 



The trachea has complete cartilaginous rings, and measures 9 cm. (3'5 in.) in trans- 

 verse, and 7 cm. (2'75 in.) in dorso-ventral diameter. Its length from the posterior of 

 the cricoid to the bifurcation is 33 cm. (13 in.), to the origin of the accessory branches 

 on the right side 15 '25 cm. (G in.). The mucous membrane lining the trachea and 

 larynx is raised into delicate regularly arranged longitudinal folds. The lungs were 

 undivided and covered with a thick whitish pleura. 



6. The Heart. 

 When seen in situ and full of blood, the heart appeared regularly conical, but on 

 removal from the body it underwent complete collapse owing to the extreme thinness 

 of the ventricular walls, instead of retaining its form, like most vertebrate hearts, in 

 virtue of the thickness and solidity of that region. In its collapsed condition it mea- 

 sured 35"5 cm. (14 in.) from the apex to the origin of the pulmonary artery. The 

 average thickness of the left ventricle was 1'6 cm. (fin.), that of the right 1 cm. (f in.), 

 and that of the septum ventriculorum 1'8 cm. (I'l in.). The diameter of the aorta at 

 its origin was 7 cm. (2-75 in.). The position of the ductus arteriosus was clearly 

 marked by a conspicuous depression on the inner wall both of the aorta and of the 

 pulmonary artery. 



7. The Urinogenital Organs. 



The kidneys are subequal, about 39 cm. (15 5 in.) long by 15-25 cm. (6 in.) wide, 

 and are composed of lobules averaging 1-3-1-8 cm. (0-5-0-75 in.) in diameter. 



The bladder (PI. L. fig. 9) is fusiform, and, after moderate distention with alcohol, 

 measures 19 cm. (7-5 in.) by 5-25 cm. (2-16 hi.). To the apex is attached a well- 



