GILLED SALAMANDERS. 



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order. In addition to this primary feature, they are characterised by the absence 

 of the upper jawbone or maxilla, although the premaxilla is present, and, like the 

 lower jaw, furnished with teeth. There are no eyelids, and the bodies of the 

 vertebrae are cupped at both extremities. There are differences in the external 

 form of the two representatives ; the olm being a long, snake-like creature with 

 small limbs, whereas the American species resembles a salamander. 



Known for more than a couple of centuries, the remarkable 

 creature to which Oken gave the name of olm is the sole representa- 

 tive of its genus, and is technically known as Proteus anguineus. From its American 

 ally it is distinguished by its elongated snake-like body and small and widely 



Olm. 



the olm (§ nat. size). 



separated limbs, of which the front pair are provided with three, and the hinder 

 with only two toes. The eyes are concealed beneath the skin, the small tongue is 

 free in front, and the palatal teeth are small and arranged in a double series. In 

 the typical form from Carniola the head is elongate, with a long and narrow 

 muzzle, truncated at the tip ; the mouth being small, with large lips. The short 

 and much compressed tail is provided with a fin, and rounded or bluntly pointed 

 at the tip. The smooth skin is marked by twenty-six or twenty-seven grooves, 

 corresponding to the ribs, and is uniformly flesh-coloured, with coral-red gills. In 

 a variety from Dalmatia the snout is longer and narrower, and the number of 

 costal grooves only twenty-four ; while in a second variety, inhabiting Carinthia, 

 the whole form is stouter, the head shorter, with a rounded muzzle, and the 

 number of costal grooves twenty-five. There is also a certain variation as regards 

 colour, apparently largely depending upon the amount of light to which the 

 creatures have been exposed ; some examples being reddish brown, and others 

 •darker with bluish black spots. The usual length is about 10 inches. 



