OCR Text |
Show 1885.] GERMAN RIVER-FROG. 669 nearly smooth. The glandular lateral fold is moderately prominent and constantly broad, as broad as or even broader than the upper eyelid. The coloration is far less variable than in the typical R. esculenta. In the normal condition the ground colour of the upper parts is olive or bronzy-olive, with the vertebral band, the fore limbs, and the sides of the head and body pale green or pale olive. But, of course, through the play of the chromatophores, the same individual may pass successively from a very light to a very dark hue, according to its being placed in very dry or very moist surroundings. In specimens long kept in the water, the colour turns to a very dark bronze-olive, almost blackish, in which case the a, b. B. ridibunda, Berlin; c. B. esculenta, Berlin; d. B. esculenta, Basle; e. B. esculenta, Diisseldorf. normally darker markings may assume a brighter greenish tint ; but if these markings are examined with a magnifying glass, they are seen to be black beautifully powdered with gold. The vertebral band varies considerably in width, and may be absent altogether. The glandular lateral folds are usually not conspicuously lighter-coloured, though sometimes metallic bronzy. The spots on the back and flanks are more or less numerous, and the hind limbs are transversely banded, but these markings are of a blackish-olive or bronzy-brown, and never of an intense black as is frequently the case in R. esculenta. The dorsal spots sometimes form pretty regular longitudinal series, but are never confluent into longitudinal bands. A dark canthal and supratemporal streak is usually present, and the latter portion sometimes expands into a regular temporal spot. The edge of the upper lip is either spotless or with a series of blackish spots which very seldom unite to form a labial streak. The cross bands on the legs may be very irregular or absent. The hinder side of the thighs, i e. that part which is concealed by the legs when the animal is at rest, are whitish or pale greenish marbled with dark olive or bronzv, or of the latter colour with or without small light |