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See also:NEWT (a corrupted See also:form from " an evet " or " an effet," a See also:term of Anglo-Saxon origin, still used in many parts of See also:England) , the name usually applied to the aquatic members of the See also:family Salatnandridae which constitute the genus Molge, formerly known as See also:Triton . But the name Triton, applied to these Batrachians by N . Laurenti (1768), has already been used by See also:Linnaeus (Systema Naturae) for parts of the See also:barnacle (Lepas anatifera) . B . Merem (182o) proposed to substitute for it the name Molge, said to be derived from the Gr . MOX.ytis or Marts, " slow," in allusion to the movements of these animals on See also:land . The similar name Molch designates these Batrachians in See also:German . The newts are very closely related to the true Salamanders, Salamandra, from which they differ principally in the shape of the tail, which is compressed, in relation to their aquatic habits during a considerable See also:part of the active See also:period . Their aquatic progression is effected principally by means of the tail, and during the See also:act of See also:swimming the legs are turned backwards and folded against the See also:body and tail, so as to admit of the smallest possible degree of resistance . A very marked sexual dimorphism prevails in most See also:species of this genus, the See also:males being more brilliantly coloured than the See also:females and provided with a dorsal See also:crest which attains its greatest development during the breeding See also:season, lasting through the See also:spring and the See also:early summer . Later in the season the males more or less completely lose their crests and other nuptial ornaments, and the two sexes are more alike; they then retire on land, concealing themselves under stones, logs of See also:wood, or 1n holes in See also:damp See also:earth, but leaving their See also:retreat at See also:night or in wet See also:weather to See also:search for earth-See also:worms and slugs which constitute their See also:principal See also:food . In the See also:water they are very destructive of tadpoles, See also:insect larvae and crustaceans .
A remarkable feature of the newts, which they See also:share with the other tailed Batrachians and the larvae of the frogs and toads, is the See also:great facility with which they regenerate, lost parts, such as the tail, limbs, and even the See also:eye, a See also:faculty which has given rise to a great variety of experiments, from the days of See also:
The male then emits, at See also:short intervals, in front of the female, several conical or See also:bell-shaped spermatophores (a gelatinous secretion from the See also:cloaca), adhering to the ground and crowned by a spherical See also:mass of spermatozoa, which the female afterwards gathers in the lips of her cloaca either by See also:mere application or by holding the spermatophore between her See also:hind legs and pressing the, mass of spermatozoa into the cloaca, whence they ultimately find their way into the See also:lower part of the oviducts, where the eggs are fecundated as they descend
.
The larvae are provided with three pairs of See also:long, fringed, plume-like See also:external gills, which are not lost until the very last stages of the See also:metamorphosis, and, in exceptional cases are even retained through-out See also:life, the newt breeding in the branchiate See also:condition, as often happens in the axolotl
.
The fore limbs are See also:developed before the hind limbs
.
The genus Molge has a wide See also:distribution, extending over See also:Europe; See also:north-See also:west See also:Africa, See also:south-western See also:Asia, eastern temperate Asia (See also:China and See also:Japan) and North See also:America as far south as See also:southern See also:California and the Rio Grande del Norte
.
Twenty species are distinguished
.
The See also:British species are the crested newt (M. cristata), the common newt (M. vulgaris) and the palmated newt (M. palmata)
.
The first is the largest, and See also:measures 4 to 6 in
.
The skin is more or less rugose, with granular warts, a strong See also:fold extends across the See also:throat, and the male is provided with a very high dentate dorsal crest which is interrupted over the sacral region; the upper parts are dark, with more or less distinct See also:black spots; the sides are speckled with See also: A . Boulenger, See also:Catalogue of See also:Batrachia Gradientia s . Caudata (1882) ; J. de Bedriaga, Lurchfauna Europas, II . Urodela (1897); F . Gasco, Sviluppo del Tritone alpestre," See also:Ann . Mies . See also:Geneva, xvi . (188o) ; E . Zeller, " Befruchtung bei den Urodelea," Z . Wiss . Zool. xlix . (1890) and li . (1891); M . Rusconi, Amours'See also:des Salamandres aquatiques (1821) ; W . Wolterstorff, " Ober Tritonblasii," Zool . Jahrb., Syst., xix. p . 647 (1904) . |
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