OUCELLA. 361 



and is gradually exposed as far as the dorsal fin, but the tail flippers are rarely 

 visible. The act of breathing is rapid, so much so indeed that it requires a very 

 expert marksman to take aim and fire before the animal disappears. I have observed 

 some of them disporting themselves in a way that has never yet been recorded of 

 Cetacea, as far as I am aware. They swam with a rolling motion near the surface, 

 with their heads half out of the water, and every now and then nearly fully exposed, 

 when they ejected great volumes of water out of their mouths, generally straight 

 before them, but sometimes nearly vertically. The sight of this curious habit at 

 once recalled to me an incident in my voyage up the river when I had been quite 

 baffled to explain an exactly similar appearance seen at a distance, so that this 

 remarkable habit would appear to be not uncommonly manifested. On one occasion 

 I noticed an individual standing upright in the water, so much so that one-half 

 of its pectoral fins was exposed, producing the appearance against the background 

 as if the animal was suj)ported on its flippers. It suddenly disappeared, and again, 

 a little in advance of its former position, it bobbed up in the same attitude, and this 

 it frequently repeated. The Shan boatmen who were with me seemed to connect 

 these curious movements with the season — spring — in which tlie dolphins breed. 



Food. — The food of the Irawady dolphin is apparently exclusively fish. 



The fishermen believe that the dolphin purposely draws fish to their nets, and 

 each fishing village has its particular guardian dolphin which receives a name com- 

 mon to all the fellows of his school ; and it is this superstition which makes it so 

 difiicult to obtain specimens of this Cetacean. Colonel Sladen has told me that suits 

 are not unfrequently brought into the Native Courts to recover a share in the 

 capture of fish, in which a plaintiff's dolphin has been held to have filled the nets of 

 a rival fisherman. 



Buccal cavity. — At the angle of the mouth the buccal cavity is closed by a well- 

 marked fringe or fold of the lining membrane opposite to the root of the tongue 

 and marking the point at which the skin- coloured palatal surface ceases. This fold 

 has the appearance as if it were able to shut off the true buccal cavity from the 

 portion immediately posterior and which is chiefly subservient to respiration. This 

 arrangement and the circumstance that the teeth are ground down to flat surfaces 

 would seem to indicate that the animals crush their food, and the presence of this 

 fold may also account for the curious and remarkable habit mentioned above, as it 

 would by shutting off the pharyngeal cavity permit of the mouth being filled with 

 water. The base of the tongue opposite to the fold is defined by a concentric fm^row 

 backwardly directed, the two opposite extremities of which correspond to the angles 

 of the mouth. In this furrow there are the large patulous orifices of racemose 

 glands as in 0. brevirostris. Posterior to the furrow, scattered over the floor and walls 

 of the fauces, there are numerous minute orifices of racemose glands. Occupying a 

 similar position to these structures, but confined chiefly to the middle of the tongue, 

 there are many transverse fine wavy lines of different lengths, but not exceeding half 

 an inch, while their breadth is about one-fortieth of an inch. To the touch they 

 l|.ave a gritty feel, but in appearance they are wavy and moniliform, as if they were 



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