156 



DR. SIDNEY F. HARMER ON CETACEA 



also " teuthophagous," has a specially strong series of teeth in its 

 lower jaw. 



(8) Killer or Grampus (Orcinus orca L.). 



A single record, May 1916, from the Sol way Firth. The 

 specimen, a male, was unfortunately incomplete, but the part 

 remaining was 25 ft. 6 in. long; and the animal must have been 

 at least 30 feet long when alive. The species is very common on 

 the Norwegian coast (Hjort, 1902, p. 120). 



It has been pointed out by Liitken (1887, p. 367) that a very 

 remarkable alteration in the proportions of the fins takes place 

 during growth in male Killers. While in young males, and in 

 females throughout life, the fins are relatively small and weak, in 

 the males all the fins —pectoral, dorsal and caudal — become 

 disproportionately larger as the animal grows older. The 

 difference between the small pectoral fins of the young male and 

 those of the old male is described by this author as being " per- 

 fectly astonishing." These alterations in the fins have more 

 recently been described and figured by Grieg (1906, p. 9; see 

 especially his figs. 2-6, showing alterations in form and size of 

 the dorsal, caudal, and pectoral fins). 



The specimen from the Solway Firth was an excellent illus- 

 tration of these statements. The dorsal fin was about 5 ft. 6 in. 

 in height, while the pectoral limbs were 6 ft. 8 in. long and 

 3 ft. 7 in. broad ; thus greatly exceeding in absolute size those of 

 a large Sperm Whale. While the pectoral limbs of young 

 animals and of females generally measure about one ninth of 

 the total length of the animal, those of the old males are as 

 much as one fifth of the entire length. Assuming the correctness 

 of this statement of Liitken's, the total length of the old male 

 here recorded would have been well over 31 ft. It seems 

 probable that the female of this species hardly exceeds half the 

 length of the largest males. The failure to recognize the 

 occurrence of these changes in the males has resulted in the 

 introduction of more than one specific name for the Killer. 



Grieg (1906) has given an account of a school of about 47 

 Killers which were observed on the Norwegian coast at the 

 middle of January, 1904. Four of the females were ascertained to 

 be pregnant, and others were accompanied by a calf. The young 

 of 2*5 m. in length were regarded as not more than 2 months 

 old, and those measuring 3'5 m. as being probably 1 year old. 

 Birth and pairing are believed by Grieg to take place during the 

 later months of the year. 



0. orca may be easily. recognized by its very large teeth, which 

 have a basal diameter of as much as 1| or even \\ in. and are 

 10 to 13 in number on each side of each jaw, as well as by its 

 strikingly marked black and white (or yellowish) coloration. 

 A white patch behind the eye is characteristic, and the white 

 area of the ventral surface, although variable in extent, typically 



