102 A NATURALIST IN BORNEO 



found in the same situation as the Sea-Snakes, and are 

 of approximately the same size. The adult, which is 

 more capable of taking care of itself and a good deal 

 larger than an average Sea-Snake, is frequently found 

 at some distance from the sea, and is not conspicuously 

 banded. A young specimen of this species was caught 

 in a cast-net at the mouth of the Sarawak River, and 

 when it was brought to me I was so convinced that I 

 had to deal with one of the poisonous Hydrophiince, that 

 I exercised the utmost caution in transferring it from 

 the net to a jar of spirit, and only discovered that my 

 caution was unnecessary when I attempted some days 

 later to identify the species. The habit of the Cobra 

 and Hamadryad of rearing up the head and expanding 

 the hood is simulated by more than one species of 

 non-poisonous snakes. Mr. H. N. Ridley records * of 

 Macropisthodon rliodomelas that when irritated " it 

 sits up after the manner of a cobra, and seems to 

 flatten out its neck as if it was trying to imitate that 

 species, while from the bluish patch on its neck are 

 exuded some drops of a white viscid liquid represent- 

 ing the well-known cobra marks. I noticed that my 

 dog, seizing this snake in its mouth to worry it, pre- 

 sently foamed at the mouth, as if he had been licking 

 a toad, and soon dropped the snake." The Macr- 

 opisthodon is not coloured at all like a Cobra, being 

 terra-cotta with a black V on its neck and a black line 

 down the back, but the dilatation of the neck and the 

 rearing-up of the anterior part of the body are certainly 

 Cobra-like habits. Just as in the Cobra, this attitude 

 is a warning signal advertising the poisonous bite, so 

 in the Macropisthodon the same attitude advertises the 

 1 Journ. Roy. As. Soc. S. BY., No. 32(1899), p. 198. 



