196 



BULLETIN 34, UNITED STATE8 NATIONAL MUSEUM. 



lack the red spots, and others have paler bellies, resembliug thus the 

 darker Fuscae. The size is tiie same. 



Fig. 49. Desmognnthus fusca auricnlata. Jfo. — . ; f. 



Ill the young of B.fiisca there is a series of pinkish iiicoinpletcly 

 separated alternating spots, in two series, covering the whole dorsal 

 region; they are rarely so well distinguished or so bright as in the 

 specimen of the same which furnished the type of ITolbrook's S. quad- 

 rimaculata. The pink fades to orange brown or ochcr, and to pale brown, 

 wath age, and at the fullest maturity all are lost in a uniform blackish 



Measurements of No. G832, in inches. 



Inches. 



Length axial, from suout to rictus oris 3 



Leugtb, axial, from soout to axilla 71 



Lengtb, axial, from snout to groin 1.95 



Length, axial, from snout to end of vent 2. 3 



Length, axial, from snout to end of tail 4. 6 



Length of fore limb 42 



Length of fore foot 15 



Length of huul limb 62 



Length of hind foot 2(5 



Width of sole foot 16 



Width of head at rictus oris :575 



Width of body at middle 55 



Habitat, etc. — This species lives chiefly among the stones in the many 

 shallow rivulets and springs of the hilly and mountainous regions 

 of the country. It is not so partial to deei)er and stiller waters as the 

 Spelerpes ruber, but prefers the rapid and sliallow streamlets; here it 

 may be found under every stone, or its delicate larva may be observed 

 darting rapidly from place to place, seeking concealment among mud 

 and leaves. The B.fmca is one of the most active and vigorous of our 

 species. The peculiar structure of the tenqxjral muscle and its ten- 

 dons, and of the occipital condyles, with the strength of the bones of 

 the front, enable it to burrow among stones and in earth iuore readily 

 than the species of other genera. When pursued, it runs and wriggles 

 out of sight with the greatest ra[)idity, and is quickly concealed by as- 

 sistance of its dusky colors. 



Professor Baird originally noticed the curious disposition of the eggs 

 in this species, which I have verified on a few occasions. As in the 



