Orca gladiator, La Cépede. 



A, 



Jthough this Odontocet, according to P. J. van Ben eden'), was known as long ago as in Pliny's time, and is named 

 hv all older naturalists who have turned their attention, to any great extent, to the Cetacea, yet the question as to whether 

 this „tyrannus Balænarum", as Fabricius calls it, is represented by one, two, or three species in the North Atlantic 

 Ocean, has only in the last decennium, we may venture to say, approached a solution. While Lutken=) considers Orca 

 gladiator and Orca minor (Schlegelii) as one and the same species, and leaves the subject of Orca Eschrichtii 

 untouched, being inclined to look upon it as a separate species, P. J. van Bene den (1. c) goes much farther in the 

 dentification of the various species. He says: „Non seulement nous croyons de voir rapporter tous ces Orques des mers 

 d'Europe å une seule et méme espece, mais nous croyons de plus pouvoir y rattacher les Orques du Pacifique, comme ceux 

 Me nos antipodes." 



As far as I am aware, very little is known about the embryos or fætuses of this species. 



Melchior (Den danske Stats og Norges Pattedyr, 1834, p. 281) makes a remark about its breeding, and states 

 that in 1829, three grampuses were killed on the coast of Jutland, one of them being a 20 ft. long female, which bore 

 ,,a fully-developed fo'tus of the size of a full-grown porpoise" (i. e. 6 ft.). His statement that it breeds in the autumn, and, 

 like the generality of whales, gives Ijirth to only one young one, is repeated by many subsequent writers. 



Sir William Turner describes a fretus, 36 inches long (ca. 0.94 metre). 



Although I can say nothing about the earlier stages of the Orca's developement, I thought it incumbent on me 

 to make use of the exceptionally copious material which the Bergen Museum contains for the investigation of Orca fætuses 

 in the later stages, and to give an account of the developement of the outward form and colouring. 



The following fætuses from tlie Bergen Museum have served as types in the present description: 



A female faHus, 408 millim. long (from Bildøen, in the beginning of Feb. 1885). 



A male fcetus, 615 millim. long (from Bildøen, Feb. 188.5). 



A female fætus, 875 millim. long (from Bildøen, Feb. 1885). 



In addition to these, I subjoin a description of a young one, taken on Jan. 26th 1891. It is 2.51 metres in 

 length, and its age may be computed at from 1 to 2 months. The animal's skin has been stuffed, and its skeleton placed in 

 the Universitv Museum in Christiania. 



I. The 408 millim. long female Orca embryo (PL V, fig. 1) exhibits some amount of fretal head-fle.xure. The 

 Orca character is already apparent in the short, thick snout, the rounded shape of the bead, the short, almost straight mouth 

 fissure, and the blunt, leaf-like pectoral fins. The long axis of the head forms an obtuse angle with the long axis of the 

 body, and its length amounts to rather less than ^/t of the length of the body. The snout portion of the convexly rounded 

 upper jaw. with 4 IVetal hairs situated far above the cleft of the mouth, is short and thick. The upper convex line of 

 contour of the head forms a concavity at the external nasal aperture (see PI. V fig. 1). The cleft of the mouth is short 

 and straight. The eye fissure lies more than 1 centim. higher than the angle of the mouth. The distance between the 

 eye and the ear aperture amounts to \/i: or 'As of the length of the trunk (in the full-grown animal to V12, according to 

 Lilljeborg). The posteriorly concave nasal orifice lies in a hollow and is bordered by raised Hps. The transversal 

 plane through the nasal aperture intersects the anterior angle of the eye. 



1) Histoire naturelle des Deli)liimdes des Mers d'Europe, 1889. p. 33. 



^ Kritiske Studier over nogle Tandlivaler, etc. Danske Vid. Selsk. Skr. 6te Række, naturv. — m.itheni. AtVI. IV — 6. 



