OCR Text |
Show 614 MR. G. A. BOULENGER ON THE [Nov. 17, 11. BUFO CALAMITA, Laur. (Plate XLVI. fig. 6.) The tadpole of the Natterjack differs from that of the Common Toad in the narrower mouth, which measures less than the interocular space and a little more than the distance between the nostrils ; the somewhat more convex upper caudal crest; and the lesser length of the second series of upper labial teeth, which is very broadly interrupted in the middle. Black above, sides and belly dark lead-grey, with pale bronzy dots; caudal crests grey, finely speckled with black; throat and chin sometimes whitish ; the light vertebral line, characteristic of this species, sometimes present before the appearance of the fore limbs. This is the smallest European tadpole, seldom reaching the length of 30 millim. recorded by Bedriaga. The following are the measurements of the largest of hundreds of specimens examined by me:-Total length 25 millim.: body 10, width of body 7; tail 15, depth of tail 5. I have seen recently transformed young measuring only 7 millim. from snout to vent. The only figure ever given of this tadpole is that accompanying Lataste's description (Actes Soc. Linn. Bord. xxx. 1876, p. 297, pi. xi. figs. 1-3) ; the mouth is described and figured by Heron Royer and Van Bambeke (/. c. p. 295, pi. xxiv. fig. 1), and detailed descriptions are given by Bedriaga (Bull. Soc. Nat. Mosc. 1889, p. 406, and ' Larves des Batraciens de Portugal,' Coimbra, 1891, p. 10). The habitat of Bufo calamita extends from the extreme West of Europe1 to Western Russia, the species becoming gradually scarcer or more local from West to East; it is entirely absent from Italy and South-eastern Europe. The breeding-season lasts from the middle of April to the middle of July ; it is by no means unusual to find in June and in the beginning of July, together in one and the same spot, ova, tadpoles, and recently transformed young of this species. 12. PELOBATES FUSCUS, Laur. (Plate XLVI. fig. 7.) Length of body once and a half to twice its width, two thirds to one half the length of the tail. Nostrils a little nearer the eyes than to the end of the snout. Eyes on the upper surface of the bodv, equidistant from the end of the snout and the spiraculum, the distance between them at least twice, sometimes nearly three times as great as that between the nostrils, and considerably greater thau the width of the mouth. Spiraculum on the left side 2, directed upwards and backwards, equidistant from either extremity of the body or a little nearer the anterior extremity, visible from above and from below. Anal opening median, a little larger than the spiraculum, and close to the body. Tail twice and a half to thrice and one 1 From Scotland and Ireland to the South of Spain. 2 Heron Royer (Bull. Soc. Zool. France, 1884, p. 162) has recorded two interesting teratological cases in this tadpole: one with two spiracula, the other with the spiraculum on the right side instead of the left. |