1920.] Dr. Malcolm Smith : Sea Snakes. 15 



32—37, usually 33—35, scales round the neck, 39 — 47, 

 usually 42 — 45, round the body. Ventrals 276 — 325. 

 Average 297. 



Colour. — Greyish or greenish-grey above, yellowish 

 white below, with from 55 — 68 dark grey or blackish annuli, 

 which may be incomplete \entrally. Head black to dark 

 olive, with a yellow band across the snout and continued 

 back along the sides of the head. Sometimes a few yellow 

 spots un the frontal and parietal shields. With age all the 

 markings lose definition, but both this form and the 

 succeeding one are more prone to keep their markings in 

 adult life than the typical form. 



H. t. aaqaardi represents a race intermediate between 

 H. t. iypica and H. t. siamensis, resembling more the for- 

 mer in scalation and the latter in colour. But for the 

 discovery of this form, I should still have regarded H. t. 

 .siamensis as a species distinct from H. t. typica. 



AH the specimens were taken in deep clear sea water, 

 being caught in trawling nets, some as far as 20 miles from 

 the coast. I have much pleasure in naming this subspecies 

 after Mr. C. J. Aagaard, of the Bangnara Rubber Estate, 

 Patani, to whom I am indebted for so fine a series. 



Two other specimens, Nos. 1276, 1175, taken off the 

 same coast and in company with typical specimens of H. t. 

 aagaardi, must be mentioned here. They have 34 and 37 

 scales round the neck, and 43 and 51 round the body 

 respectively. Ventrals 302 and 292. Both are females and 

 both have two superposed temporal shields on both sides. 

 In other respects they agree entirely with H. t. aagaardi. 



No. 1276, with 43 scale rows I should have referred 

 without much hesitation to this form, for the same variation 

 in the temporal shields is to be found in its northern ally 

 H. t. siamensis. No. 1175, with 51 scale rows — no, less 

 than 4 in excess of what is to be found in any other specimen 

 of my series — is not so easily disposed of. For the present 

 I regard them both as aberrant examples of H. t. aagaardi. 



Hydrophis torquatus siamensis Smith. 



Hijdrophis tiiberciilatus, Smith, Journ. N. H. S. Slam, I, pp. 

 214, 247 (191.")). 



Hydrophis siamensis, Smith, J. N. H. S. Slam, II, p. 341 (1917) ; 

 idem, Journ. Bombay N. H. S., XXVI, p. 682 (1919). 



Similar to H. t. torquatus, but with fewer scale rows 

 round the neck and body, greater average number of 

 ventrals, larger average frontal and darker colour ; also in 

 a tendency of the temporal shield to subdivision. 



Type. — Adult male, author's number 1151, collected 

 at Ban Yao, Inner Gulf of Siamv Sept., 1917. 



Number of specimens examined, 84. 



Variation. — The frontal shield is as long as its distance 

 to the rostral in about 50% of the specimens ; in the 

 remainder it is shorter, with two exceptions, in which it is 

 nearly as long as its distance to the end of the snout. The 



