10 PROFESSOR STRUTHERS. 



to a little within the edge of the opening, where the walls 

 of the pouch and all the parts within it become white or 

 cream-coloured. Plugging the mouth of the pouch is a large 

 soft projection like the pulp of the thumb, as if a distended 

 septum, but the lining membrane of the pouch dips in half an 

 inch before and behind it, the depth of the pouch being about 

 1J inch at other parts. The nipple is brought into view by 

 pushing aside the septal plug or the outer wall of the pouch, as 

 seen in the figure. The nipple, flattened sideways, projects like a 

 thick tongue, f inch in height, \ inch in breadth. On the outer 

 side of the nipple, a little way from the summit, is a large 

 aperture, admitting a goose-quill, shortly within which two 

 apertures are seen, as if the main duct there divided. Into 

 one of these a middle-sized probe passed readily for 1J inches. 

 The whitish epithelium on the median plug and nipples was 

 about 2*0 i ncn thick, and when this was removed, the cutis vera 

 on the summit of the plug and nipples presented tufts instead 

 of the fine filiform processes which their other parts showed. 

 In one of the photographs, taken the day after the whale was 

 beached, the median plug can be recognised bulging moder- 

 ately in the mouth of the pouch. 



9. THE PLAITINGS OF THE SKIN. These are much broader 

 and consequently fewer than in other finners. The breadth is 

 about 4J, or maybe 5, inches. The furrows, after a few inches, 

 have gained a depth of 1 inch and reach a depth of 2 inches, 

 some 2J, and are dark to the bottom. The number of plaits is 

 about twenty-four. They extend from below the lower jaw to the 

 front of the belly, ending there on a line drawn from 2 feet behind 

 the axilla to the umbilicus. Two of the furrows, the 2nd and 

 7th below the axilla, are not continued forwards ; the same of 

 the llth, but it is longer. The median furrow is not continued 

 so far back as those next it. There is a short (13 inches) azygos 

 furrow to the right side of the umbilicus, which if continued 

 forwards would have split the median plait. The line seen in 

 fig. 5 above the shoulder is not one of these furrows, but only 

 a fold of the skin. The system of furrows begins below the 

 side of the mandible, below the labial groove, by two furrows, 

 closed at each end, as shown in fig. 5. The furrows of the 

 throat run forwards close to the mandible, within 2 inches of it, 



