16 



BULLETIN 36, UNITED STATES NATIONAL MUSEUM. 



existeiice iu S. leniiginosa of (1) a relatively longer beak, (2) flatter 

 intermaxillaj (3) a longer tooth-row, aud (4) more numerous teeth, I find 

 (5) that the symphysis of the mandible is longer than ia 8. gadamu^ 

 (G) the temporal fossae are larger, (7) the pterygoids are longer, and (8) 

 the interorbital breadth less (see table of measurements below). The 

 -whole relative arrangement of the bones of the inferior surface of the 

 skull differs iu the two species. 



In regard to external appearance, if the figures published by Sir 

 Kichard Owen are to be relied upon, the two species, S. lentiginosa and 

 S. gadamu, are very different (T. Z. S., vi, 1866, pi, 3 {8. gadamu)^ pi. 5, 

 figs. 2, 3 {8. lentiginosa). In addition to the difference iu color and 

 style of marking, the proportions of the pectoral fin, as presented both 

 by the measurements aud in the plates, are such as would alone suflSce 

 for the separation of the two species. The length of this member in 8. 

 gadaimi is fully 22 i)er cent, of the entire length of the animal, while in 

 8. lentiginosa the former length is less than 13 per cent, of the latter. 

 Ijifterences of almost equal magnitude exist in the proportions aud rela- 

 tive positions of other members of the body. The value of these dis- 

 tinctions, however, would be greatly enhanced if we could be sure that 

 the measurements were derived from the specimens themselves and not 

 from the drawings. [Jnfortunately the intimation derived from the first 

 paragraph of Sir Eichard Owen's paper is that they ^ere derived from 

 the drawings. Even should such prove to be the case, the differences in 

 the skulls remain, aud these alone, in my estimation, are sufficient to 

 warrant the separation of the species. 



*Thi.s is the extent of the rousn.so area; the real syinpliy.sis is about 5.3 cm 



