1903.] and OrtJiogenctic Valuation in Lizards, etc. 115 



C. GUTTATUS VAR. SiRiATA (fig. 2). The young of the first year are 

 decidedly dark above ; only the first pair of stripes is white, although 

 thin and sometimes vanishing towards the arms ; the other stripes are 

 so little pronounced that they appear only under certain lights as 

 greenish bronzy bands, somewhat lighter than the ground colour. 



Older specimens exhibit variation from 6 to 7 or 8 white stripes, 

 even with an incipient 9th, and these variations can be grouped as 

 follows : 



Staye A. 6 Stripes. In a specimen 80 mm. in length the third pair 

 of stripes is united on the neck. The enclosed midfield is dark and 

 shows very faint, pale mottlings, due to an irregular double row of 

 spots on the lumbar region and lower back, confluent on the middle of 

 the back. 



Stage B. The 3rd pair of stripes forms parallel lines. On the mid- 

 field conspicuous white spots form a double row on the middle of the 

 trunk, single, by confluence towards the shoulders. Further modifica- 

 tion of this double central row (equivalent to stripes 4) leads either to 

 Stage Cor to D. 



Stage C. 7 White Stripes. The central stripe, formed by fusion of 

 the double row, is composed of white beads, or beads and a continuous 

 stripe of variable extent. 



Stage D. 8 White Stripes. The double row is joined into one on the 

 neck, but is continued over the back in two conspicuous lines, 4-4, 

 which on the lumbar region are each dissolved into a row of spots. 



Stage E. 9 White Stripes. The same as D, but in the mid-line of the 

 back, or on the lumbar region, has appeared a short row of white spots, 

 indicating a 5th unpaired line. 



In older specimens the first pair of lines becomes faint and shortens 

 from before backwards, and lateral spots, below this line, appear in two 

 rows. Additional small spots make their appearance near the tail 

 and on the lumbar region in the dark fields between the lines 1 2 and 

 23. 



The colour of the under parts varies but little : yellowish-white in 

 the females, suffused with pale blue in the males, and the latter have 

 always a narrow blackish collar. 



C. GUTTATUS VAR. GUTTATA (fig. 3, PI. 4). The important features 



of this very dark race are the complete breaking up of the 4th and 3rd 



pair of lines into whitish-yellow spots, the breaking up and fading of 



the 2nd and 1st pair of lines, and, lastly, the complete disappearance 



of the spots from the root of the tail forwards over the lower back. 



These changes are gradual and proceed regularly with age. 



In very young specimens all the underparts are uniformly white, 



including the collar. Lines 1 and 2 above are still pronounced white 



stripes, although sometimes partly broken into short streaks, and 



fading towards the arms. The original stripes 3 and 4 are already 



