18/2.] MR. E. W. H. HOLDSWORTU ON A NEW CETACEAN. 583 



Plate XXXIV 



Fig. 1. Dudusa splungifomiis, p. 577. 



2. Geometra lineata, p. 580. 



3. alboviridis, p. 581. 



4. Odontoptera chalybeata, p. 580, 



5. Chilo interruptellus, p. 581. 



Fig. 6. Ckilo inconspicwllus, p. 582. 



7. cervinellus, p. 581. 



8. bivitelhis, p. 581. 



9. Jartheza biplagella, p. 582. 



6. Note on a Cetacean observed on the West Coast of Ceylon. 

 By E. W. H. Holdsworth, F.L.S., F.Z.S. 



[Received April 9, 1872.] 



Whilst becalmed a few miles off Chilaw, on the west coast of Ceylon, 

 on the 7th of April, 1868, my attention was attracted by hearing, not 

 far from the vessel, the blowing sound usually produced by Cetaceans 

 when they have come to the surface to breathe. I found that the noise 

 proceeded from a small Whale, which was lying motionless, with its 

 back exposed, not more than fifty yards from the vessel. The first 

 flaws of the sea-breeze had not yet appeared on the water, and the 

 surface was undisturbed by even a ripple. It was a favourable time 

 for observation ; and as I had a good binocular glass and my note- 

 book by my side, I was at once able to observe distinctly and to sketch 

 that portion of the body of the animal which was seen above water. 

 From first to last, it was more or less visible for four minutes ; and 

 during that interval it blew five times. The whole animal was not 

 seen ; but from such parts of it as rose at different times above the 

 surface it appeared to be about twenty-five feet long, with a rounded 

 back and a rather thick body. Its most remarkable feature, and the 

 one to which I wish especially to direct attention, was the dorsal fin 

 (fig. 1, p. 584), which could not have been less than five feet high, 

 standing erect on the highest part of the back and shaped like the 

 pointed extremity of an ordinary sword, with the anterior edge slightly 

 convex and the posterior straight. After breathing, the animal very 

 slowly sank in a horizontal position till only half the dorsal fin was 

 left exposed ; and so it remained for about thirty seconds, when it 

 again came to the surface and blew as before ; this was repeated four 

 times after its first appearance, before the animal finally went down. 

 The profile of the head was not entirely seen, so that the shape of 

 the nose, whether beaked or otherwise, could not be ascertained j but 

 the top of the forehead, when looked down upon from behind as the 

 animal rose head first on one occasion in an altered position, presented 

 a broad rounded outline (fig. 2), with an indentation in the centre 

 leading to a distinct longitudinal depression on the top of the head, 

 in which the blow-hole was placed. The alteration in the position of 

 the animal from broadside to nearly end-on enabled me to see also 

 that the dorsal fin had the thin flattened shape (fig. 3) usual in that 

 appendage. After the fifth breathing the head sank down, the broad 

 transverse flukes showed for a moment at the surface, and the animal 

 finally disappeared. Its behaviour was evidently that of a true Whale, 

 and totally unlike that of Dolphins and other small Cetaceans, which 



