6 SWED. ZOOL. BXP. TO SIAM, EINAR LÖNXBEKU, 2. LIZARDS. 



scales and a supraocular group on either side larger than other scales on the upper 

 surface of the head. A triangulär spine (compressed, but also keeled on the broader 

 sides) is situated just behind the end of the supraciliarv edge, and is flanked by 

 some smaller scales, the large one has a height equal to about 2 A> the diameter of 

 the tympanum. Behind this on either side of the nape a group of about four short 

 and stout spines. A ridge from below the eye to above the tympanum with scales 

 increasing in size behind so that a low crest of triangulär scales is formed. A strong 

 nuchal crest, separated from the dorsal. The four hindmost scales in this are the 

 largest, measuring more than the diameter of the tympanum. On either side the 

 nuchal crest is flanked by erect, strongly keeled scales produced in sharp points. 

 A transverse occipital crest on either side forms about right angle with the nuchal 

 crest, and is constituted by five compressed spine-like scales, the most mesial of 

 which is small, the fourth from the median line is the longest, attaining a height 

 more than equal to the diameter of the tympanum. These transverse occipital crests 



are flanked b)- large, erect scales which are strongly 



keeled and mucronate, and especialh' at the lateral 



end of the crest spine-like. 12 upper, and 11 or 12 



lower labials. The anterior lower labials keeled, and 



traces of keels may be seen on some other labials. 



All the scales on the interramal space strongly keeled: 



^ >LiF^- an en l ai *g e ^ series of scales on either side parallel to 



^JV the lower labials, but separated from them by 2 or 



¥> 3 rows of smaller scales. The mesial row of gular 



Fig. i. Acanthosaura horrescens. scales also enlarged, mucronate. A transverse gular 

 Nat. size. fold and an oblique fold in front of the shoulder on 



either side, all of them covered with small, but sharply 

 mucronate scales. Around the corner of the mouth and on the sides of the neck 

 numerous scattered tubercular spines. The dorsal crest, which at the anterior end 

 is completely separated from the nuchal crest, is low, and composed of a mesial series 

 of enlarged, pointed scales, and on either side of that a series of almost as large, 

 strongly carinate scales with their sharp points directed upwards and a little back- 

 wards. This condition prevails throughout the back, so that, seen from above, the 

 ridge of the back appears to be tricarinate. Scales of the back and sides small, inter- 

 mixed with irregularly scattered, enlarged scales, which are more or less strongly keeled. 

 Ventral scales Large, strongly keeled and sharply muoronate. Före limbs with large. 

 keeled scales, smaller at the elbow. Hind limb with large, keeled scales on inner and 

 anterior surface of the tigh, the outer and the posterior side of the same mosth 

 covered with small scales which are mixed with large, keeled ones. The tibia is 

 mostly covered with Large, keeled scales, but at the upper as well as at the lower 

 end areas of small scales are found near the joints. Scales of fingers and toes keeled 

 and mucronate. Third and lourth fingers equal. Tail comparat i vely slender covered 

 with Large, keeled scales, those on the lower side largest. Colour (in spirit) olive 

 brown. A broad dark hand on the sides of the head from above the nasal fhrough 



