OCR Text |
Show 1906.] IN MEXICAN LIZARDS. 361 the under surface of the tail and the whole of its terminal half all round are of an orange to almost brick-red colour. The collar is never dark. The chest and abdomen of old specimens, especially males, are suffused with greenish or faint blue, while the basal parts of the scales are blackish. After removal of the horny portion of the epidermis, which is quite opaque, the scales appear entirely blue-black.-The 61 m m . type-specimen is quite exceptional; chest and belly being much mottled with black, this pigment being almost preponderant on the chest. Upper parts'. During their growth these lizards pass through an extraordinary series of changes in their colours and pattern (text-figs. 69, 81, 82). Text-fig. 82. Cnemidophorus mexicanus typicus. A = Oaxaca No. 9. Third pair of stripes partly vanishing and cut across by the increasing pale field-patches. B = Oaxaca No. 8. Third pair of stripes restricted to faint narrow traces on the neck. C = Totolapan No. 3. Old specimen; completely tiger-barred. D = Oaxaca No. 16. „ ,, „ Stage A.-The young, up to about 50-60 mm., possesses three pairs of complete white stripes, sharply alternating with dark |