Miscellaneous. 293 



Its general tints vary between different shades of brown, olive, yel- 

 low, and light green, the last-named being the most rarely observed, 

 and the yellow being the tint usually assumed when the animal has 

 been hidden from the hght. This is the colour it always presents if 

 taken for inspection at night, and when brought into the influence of 

 lamp- light it appears at first almost white, but may soon be seen to 

 darken and some of the markings to appear. The side that is next 

 the hght will change rather sooner than the other, the changes being 

 always gradual. It has three distinct sets of markings, the first to 

 appear being two ranges of irregular distant elongated spots, which 

 may appear either as a dark tint upon the ground-colour when that 

 is light, or a light one if it be dark. These marks are never entirely 

 absent when either of the other sets is present, although sometimes 

 but faintly discernible. 



The other two sets of markings consist of an irregular marbling, 

 and a number of full round spots ; the latter never appear otherwise 

 than as dark upon the ground-colour, and the marbling, which is ge- 

 nerally also dark, only occasionally appears a little lighter than the 

 ground-colour, and then of a different tone ; either may be visible 

 without the other, or both may be distinctly traceable. Sometimes 

 the marbling will be apparent together with such of the spots as are 

 placed within its intervals, those upon the surface occupied by the 

 marbling being amalgamated with it. 



When the general colour is light yellow or pale greenish, which is 

 the case if the animal be suddenly brought into the light, the elon- 

 gated spots, which form two rows on each side, will begin to appear 

 of a very delicate purple tint. After that the marbling gradually 

 shows itself, and the general tmt begins to darken ; when some time 

 has elapsed a brown colour is assumed, and the elongate spots, at first 

 purple of a darker tint than the yellow ground-work, are seen to be 

 brown, of a lighter and rather richer tint than that which now per- 

 vades the whole. These distinctions may go on increasing, may then 

 decrease and again increase ; the spots may appear, may come and go 

 with different degrees of intensity, so that the variety of appearances 

 presented is almost indefinite. ^Tien visited in the day-time, the colour 

 is generally brown, sometimes without markings, generally with the 

 elongate spots of a lighter tint, and the marbling or the round spots, 

 or both, more or less apparent. Occasionally it presents a uniform 

 dull olive, and then has no markings. Sometimes it is of a light drab 

 colour, with the different marks faintly indicated. The ventral series 

 of prominent scales remains constantly white, as stated by Van der 

 Hoven, not participating in the changes of the surrounding parts. 



This author does not in any of his plates represent the longitudi- 

 nal rows of markings as a decided dark upon the ground-colour, nor 

 is the marbling anywhere clearly shown as pervading the whole body ; 

 neither does he give the deep brown tint with the marbling as a dark, 

 and the longitudinal rows of spots definitively marked as a light. 



I have never seen my specimen present anything like the appear- 

 ances delineated in his plates 4 and 5, probably because I have not 

 irritated it. 



