Dr. H. Burmeister on a new Porpoise. 



133 



of 25 centim. in front of the fin, as a single line of moderate spines ; 

 but soon another line begins on each side, so that in the beginning 

 of the fin there are already three lines of spines. These three lines 

 are continued over the whole rounded anterior margin of the fin, 

 and are augmented on both sides by other small spines irregularly 

 scattered, so that the whole number of spine-lines in the middle of 

 the fin is five. Towards the end of the fin they become smaller, 

 and on the rounded tip of the fin there are no spines at all. 



From the hinder margin of the dorsal fin to the notch of the 

 tail-fin is 54 centim. The tail-fin is 39 centim. broad, and each 

 fluke 20 centim. long on the anterior margin. This margin is some- 

 what curved backwards, and the hinder margin sinuated. 



The underside of the body is somewhat more curved and extended 

 than the upper side, and the tail more descending. 



The anus is situated under the beginning of the dorsal fin, 70 centim. 

 distant from the notch of the tail-fin. 



The individual seems to be a very young one, because all vestiges 

 of genital organs are wanting in the exterior. The anus has a dozen 

 radial folds, of which the largest, 6 centim. long, runs forwards; all 

 are very deep, and transversely ridged. 



The pectoral fin is falcated, 26 centim. long and 10 broad. At 

 its proximal end there are many fine ridges in the skin, and in the 

 middle part are ridges indicating the finger-bones beneath. 



The skull proves that the animal is a very young one, and that it 

 has come perhaps only to half its natural size; because all the bones are 

 very weak, not perfectly ossified, and the vomer entirely cartilaginous. 

 It has the general figure of the skull of the European Phoccena, dif- 

 fering principally in the form of the hinder part of the intermaxil- 

 lary bones, which is more abruptly elevated in this new species than 

 in the European (see figs. 4 & 5). 



Fig. 3. Fig. 4. 



Side view of the skull of Phoccena spinipinnis, reduced one-third. 



