On two subfossil Whales discovered in Sweden. 



41 



The 16 th caudal vertebra (PI. X. figg. 102, 103) is somewhat 

 smaller than the last, is destitute of arcus, and has the canalis spinalis 

 only on the sides bordered with projecting processes. As regards the fora- 

 mina for the branches of the aorta, the one of them on the lower sides, 

 namely the right, is closed, and thus for the right canal there is in the 

 lower part only one opening, in the cavity on the under side of the cor- 

 pus. At the lower part of the left side there is on the contrary a very 

 small opening besides the larger one in the under cavity. Dimensions of 

 this vertebra: Breadth of corpus in front 5\"] height of d:o d:o 5^": length 

 of d:o, without epiphyses, 2". 



The last of the discovered vertebrae, or that which we take to be 

 the 17 th caudal vertebra (PI. X. figg. 104, 105) is almost circular. There 

 are only 2 lower openings to the canals for the aorta-branches, situated 

 in the cavity of the under side. Of the canalis spinalis all that remains is 

 a very little hollow, at the bottom of which are three small foramina. Di- 

 mensions: Breadth of corpus in front 4f-"; height of d:o d:o 4| " length of 

 d:o, without epiphyses, 1|-". 



The breast-bone (PI. 11. fig. 106) presents the simple form that it 

 usually has in the Balaenidae. It is oval, longer than it is broad, the fore- 

 part rounded, and with a little concavity in the right border near the point. 

 The hinder end is pointed, so that the side-borders there form an angle 

 somewhat less than a right angle. The side-parts are very convex in the 

 middle, also rather thinner and bent obliquely upwards. It is hard and 

 solid, but the porous and thick edges indicate that it was entirely imbedded 

 in cartilage. It is particularly remarkable that that bone is so fully deve- 

 loped, and shows such considerable hardness, although other parts of the 

 skeleton show that it belonged to a very young animal, and although the 

 sternum otherwise does not ordinarily at so young an age attain such thick- 

 ness and hardness. Its dimensions are: Length 6f"; breadt 4-|-"; thickness 

 in the middle 1*". 



The three perfect ribs (PI. X. figg. 107—110 and PI. XI. fig. Ill), 

 which we may consider as belonging to the 3 rd , 4 th and 5 th pairs, are 

 particularly characteristic for this Whale, as has already been remarked. All 

 three belong to the right side. The first of them (fig. 107) is not quite 

 perfect at the lower end, but it seems to be only a very small portion that 

 is lost. In proportion to its length it seems remarkably broad at the lower 

 end, which shows that it must be one of the anteriors. The upper end is 

 much compressed and bent inwards, with a rounded-off projecting angle at 

 the upper border, without visible capitular process, for the extremity itself 



Nova Acta Keg. Soc. Sc. Ups., Ser. III. Vol. VI. 6 



