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Show 1871.] DR. J. ANDERSON ON INDIAN REPTILES. 165 to an entirely different conclusion. Mr. Gammie, however, to whcm I am indebted for these specimens, collected at m y request the supposed females of this species without determining the point by dissection ; and on examining them I find that the sex of all his supposed females is correct. The question as it now stands may* be stated thus: all the large-scaled Darjeeling Japaluree which have hitherto come under m y observation are undoubtedly males of J. variegata, while all the females of that genus from that locality only differ from J. variegata in having a mere rudiment of a dorsal crest, smaller scales, and a more sparing admixture of large ones. These characters are persistent in all the specimens of the sex that I have examined from that part of the Himalaya. The conclusion to be drawn from these facts is self-apparent, viz. that the large-scaled individuals are males of J. variegata, and that the small-scaled ones are the females ; unless it so happens that there is another species, the males of which 1 have not as yet obtained-a supposition which seems improbable, as all the specimens were collected within an area of a few miles. Dr. Jerdon's small-scaled form, which he has named J. microlepis, has a reddish back, abruptly separated from the greenish colour of the sides by a series of somewhat raised scales. I have received a specimen from Darjeeling agreeing with Dr. Jerdon's description of the coloration; but the lines of enlarged scales are prolonged into the red, and I cannot avoid thinking that in Dr. Jerdon's specimen they followed a similar arrangement, and that the appearance he describes may have been due to either one of two circumstances. I find in m y specimen that on one side the enlarged scales do not pass on to the red surface, but they do so on the other side, where they are quite as well developed as in the adjoining green surface. On passing m y finger roughly over these enlarged scales they are easily rubbed off, and no trace is left of them; and it seems probable that in Dr. Jerdon's specimens they may have disappeared from an analogous cause. Any way, however, the enlarged scales on the red surface are not so distinctly visible as on the green ; and this is to be explained by the fact that they are generally pale-coloured on the green surface, and hence in strong contrast to it; while on the red they partake of a similar hue, and are thus much more indistinct. I attach no weight whatever to the red hue of the back ; for this specimen agrees in every other point of its coloration with individuals which present no trace of it. It is highly probable, then, that this Lizard is endowed with the power of changing its colours quite as much as Calotes; and, indeed, the variations that occur in it seem only explicable by some such cause. I have carefully observed Calotes versicolor in confinement, and found it to undergo the most remarkable and almost sudden changes of colour while under the influence of fear or irritation ; and on placing the specimens in spirit the colours are retained. It is a well-known fact, too, that the species of that genus are continually adapting their colours to the surfaces over which they may be hunting ; and it is probable that they undergo chromatic changes depend-ine 'on sexual causes. With these facts before us, and keeping iu |