* NATURAL HISTORY. 411 



the surface of the earth, where no ray of light can possibly enter. 

 The eyes of this singular creature are mere points covered with 

 skin, and useless for vision ; indeed when in captivity it always 

 chooses the darkest parts of the vessel in which it is confined. 



The Proteus breathes in two ways by lungs and by gills, 

 the latter organs appearing in the form of two tufts, one on 

 each side of the neck, just above the fore limbs. The circula- 

 tion of the blood in these branchial tufts can easily be seen 

 with a microscope of moderate power. These tufts are of a 

 rather deeper pink tinge than the remainder of the body, which 

 is of a very pale flesh-colour. Exposure to light darkens the 

 tints both of gills and body. It bears some resemblance to the 

 young of the newts, which are furnished with branchial tufts, 

 which they lose upon attaining maturity, and were therefore 

 for some time thought to be the young of some unknown reptile. 

 It has, however, been proved to be a perfect animal, and has 

 been found of all sizes. 



It is easily kept in water and requires no feeding, but the 

 water must be frequently changed to keep it in health. The 

 blood disks of this animal are exceedingly large ; so large, in- 

 deed, as almost to be distinguished by the naked eye. When 

 in captivity, its movements are slow and eel-like, nor does it 

 seem to make much use of its almost rudimentary limbs. 



It has usually been found on the soft mud of a small lake in 

 the grotto of Maddalena. It is not always present, and has 

 been conjectured to be the inhabitant of some unknown sub- 

 terranean body of water, and to have been forced through the 

 crevices of the rocks. Besides the grotto of Maddalena at 

 Adelsburg, they have also been found at Sittich, thirty miles 

 distant, thrown up from a subterranean cavity. 



