Mr. A. W. E. O'Shaughnessy on Norops. 185 



Now, since the year 1840 it has been known that two 

 distinct forms of Norops exist, — (1) a lizard with a compara- 

 tively short tail, toes distinctly dilated, although not to the 

 same extent as in many species of Anolis, the head entirely 

 covered with strongly keeled scales, and long limbs, the hinder 

 ones when laid forward reaching to the tip of the snout ; (2) a 

 slenderer lizard with head more depressed and pointed, the 

 muzzle only furnished with keeled scales, those of the rest of 

 the head smooth, a much longer tail, much shorter limbs, the 

 hinder ones reaching, when laid forwards, to the ear-opening 

 only, and a bright white vitta passing along the side. 



This second form was described by Berthold in 1840, ' Ab- 

 handlungen der Koniglichen Gesellschaft der Wissenschaften 

 zu Gottingen,' 1840, p. 62, under the name of Draconura 12- 

 striata. His description is full and distinct, and accompanied 

 by a coloured figure (not very good, but showing well the 

 slenderer shape and long tail of the form in question) and a 

 diagram of the upper surface of the head, which exactly repre- 

 sents that configuration and arrangement of the shields which 

 distinguishes this species from the other. 



The shields of this part of the head are much smoother, pre- 

 sent a more regular symmetrical arrangement, and give a much 

 natter appearance to the whole surface than in the first-men- 

 tioned form. Moreover the occipital plate is an ovate, well- 

 defined shield, much larger than any other shield of the head, 

 whereas in the other form it is very small and inconspicuous. 

 There is only one series of scales between the supralabials and 

 the eye, whereas there are two in the auratus of Dumeril and 

 Bibron. 



The anterior limbs are said to reach to the tip of the snout, 

 the posterior ones to the ear. The length of the tail is said to 

 be three times that of the body. 



In a memoir, ' Ueber verschiedene neue oder seltene Rep- 

 tilien, &c.,' Gottingen, 1846, at p. 6, Berthold mentions the 

 Anolis auratus of Daudin, the Norops auratus of Wagler and 

 D. & B., as the only known species of Norops, thus regarding it 

 still as even generically different from 12-strtatus. He says, 

 " the head is covered with small, many-keeled plates ; the 

 hinder limbs reach to the mouth, the fore limbs even beyond." 

 These are clearly the characters of the form of Norops first 

 mentioned above. 



Returning to the original description of Norojis auratus by 

 Dumeril and Bibron, taken from two specimens, one from 

 Guiana the other from Surinam (or Cayenne), we find that it 

 differs only in one point from this particular form, i. e. the 

 auratus above mentioned, the shorter-tailed, longer-limbed 



