388 CETACEA. 



encircles the tube, but its two ends do not meet. Posteriorly it gives off an offshoot 

 which runs from right to left, appearing on the ventral surface of the left border of the 

 trachea. The fourth is a short cartilage on the right side of the ventral aspect of the 

 tube. The fifth encircles the trachea, though its ends do not unite, but overlap each 

 other, and the anterior border of its dorsal portion gives off a short offshoot to the left. 

 The next ring nearly twice encircles the trachea, above and below the point at which 

 the right bronchus is given off. It commences in a free end on the left border, and 

 after describing the course I have indicated unites with itself on the dorsal surface, 

 where it gives off two short branches directed backwards and to the right. The right 

 bronchus is attached to the projecting third of the fifth ring of the trachea, and it 

 commences by a cartilage which twice encircles the tube, but describing its first 

 round in a zigzag manner, leaves a vacuity at the inside of the tube which is opposed 

 to the trachea. The method of division and distribution of the fifth cartilage is that 

 which prevails on the main bronchial division. In the first part of the trachea the 

 cartilages are round and cord-like, but as they are traced backwards they become 

 relatively broader and flatter, yet thicker than those of Flatanista, and are separated 

 by rather wide intervals, so that the tube has considerable expansibility. The first 

 bronchus is 4-50 inches long before it divides. The other division is as capacious 

 as the left bronchus, and runs 3-75 inches before its division. The left bronchus is 

 2*50 inches from its division to its bifurcation. 



Lungs (Plate XXIX, fig. 2).— In the adult the base of the right lung, 

 instead of being pointed as in the left, is bevelled off obliquely from its outer 

 to its inner margin. The anterior border in its upper third is hollowed out 

 for the reception of the heart. Two small lappets above this portion overlie 

 each auricle, and the apex is only 3 inches above the arch of the aorta. The 

 extent of lung posterior to the apex of the heart measures 12*50 inches in length by 

 5-25 inches in breadth, while the total length of the organ is only 19 inches, so that 

 the great mass is posterior to the heart. This portion is concave anteriorly, and 

 corresponds to the convex surface of the liver, over which it lies, but separated by the 

 interposed diaphragm, and the dorsum of the lung is of course convex. The apex 

 has two rounded angles separated by a concave interval, and its total breadth here is 

 5 inches ; the posterior angle being twice as large as the anterior. Below the heart 

 the two lungs appear to approach each other much more nearly than in reality, 

 from the circumstance that the lower end of the cardial border of the lung is the 

 seat of a large gland (Fgl.) which projects towards the middle line along the dia- 

 phragmatic attachment of the pericardium. 



In the foetus the apex of the lung is rounded without any angles ; the base of 

 the right lung is not bevelled off, but partially divided into two lobes. 



Fulmonary glands' (PL XXIX, fig. 2 Fgl, and PL XXXVII, fig. 5).— In the 

 adult the pulmonary gland is largest on the left side. It is a triangular body 1"'50 



^ Pulmonary glands, evidently of a kindred sort, have already been recorded by Hunter, as obtaining in JbelpUnus 

 tursio; and in specimens of Olohiceps inhabiting the Chinese, American, and British coasts, respectively, by Williams, 

 Jackson, Gulliver, and Murie. In Eisso's Grampus also they have been met with by the last-mentioned observer, who, 

 moreover, has discussed their nature, and given figures of them, in position, in his Memoir on the organisation of the 

 Ca'ing Whale already cited. 



