12 THE SALAMANDER 



varies from about 120 mm. to 170 mm., according to age. Of this 

 the tail, or post-sacral region, accounts for rather less than one-half, 

 the proportion being something like 75 : 80. The males tend to be 

 rather smaller than the females, but the sexes are more easily dis- 

 tinguishable externally by the appearance of the cloaca, which is 

 quite flat in the female, but swollen and tumid in the male. This 

 difference is more marked in the breeding season, but a little practice 

 makes it readily distinguishable at any period. 



The gait of the Salamander is very blundering and clumsy, and 

 when the fore-foot is lifted from the ground the whole body is tilted 

 so as to assist the movement. Then the limb having been moved 

 forwards, the animal 'flops' over on to that side and repeats the pro- 

 cess on the other. In this way the movement at the shoulder-joint, 

 in a vertical plane, is very slight. The pelvic limb shows rather more 

 movement in this direction — nevertheless there is a strong tendency 

 for the back of the foot to be dragged along the ground as it moves 

 forward. The sector described by the femur in a horizontal plane 

 lies almost entirely anterior to the transverse plane across the aceta- 

 bula; in other words, when the femora are fully retracted they are 

 approximately at right angles to the trunk — while when they are 

 drawn forwards to their fullest extent the limb lies close alongside the 

 body. In spite of its apparent clumsiness when seen under ordinary 

 conditions stalking around a vivarium, the Salamander can at times 

 move with astonishing rapidity, this being particularly so with young 

 metamorphosed individuals. Seizing of prey, too, is performed at 

 lightning speed, and, if the range is a long one, the animal may jerk 

 its whole body in the direction of the object to be seized, thus assisting 

 the movements of its head. The Salamander is quite capable of seizing 

 a passing 'blue-bottle' in flight, and has been observed to do so. The 

 climbing powers of some individuals are also rather astonishing, and 

 it has been found necessary to keep a piece of wire-gauze over the 

 top of a glass accumulator jar some 18 inches high, which was being 

 used as a vivarium, in order to prevent the escape of the inmates. 

 This they attempted by climbing up the angles, chimney fashion. 



The colour markings are subject to great variation within certain 

 limits, some individuals being almost entirely yellow, while others 

 again are nearly black. Some have thought that the intensity of 

 colour is controllable by varying the environmental conditions, e.g. 

 background, temperature, and humidity, and further that such 

 adaptive changes are transmissible to future generations. This ques- 

 tion is one of experimental zoology rather than of anatomy, and it is 

 not proposed to discuss the matter here. The works of Kammerer, 



