98 BULLETIN 34, UNITED STATES NATIONAL MUSEUM. 



liaut; the coast species being described as brown with a gray dorsal 

 stripe, instead of black with a yellow dorsal stripe. In it the limbs 

 are not banded, and the belly is uniformly pale, contrary to what holds 

 in the present species, which is the handsomest of the genus. I ob- 

 tained four specimens of this salamander, under logs, in a swamp near 

 the head of the South Boise River, on the south side of the Sawtooth 

 Mountain range, Idaho. 



^ fy A 



3 5 



Fig. 18. Amhly stoma epixanthum, Atlanta, Idaho; \. 



This species is in all respects more robust than the A. macrodactylum, 

 and is more brilliantly colored. Its tints are those of the European 

 Salamandra maculosa^ and are brighter than those of any other species 

 of the genus. Its hyoid apparatus is represented on Plate 23, fig. 8. 



CHONDEOTUS Cope. 



American Naturalist, 1687, p. 88 (January). 



Otoglossal cartilage triangular, attached by abase to each side of the 

 hypobranchial cartilage. 



In other respects this genus agrees with Amblystoma. The larva of 

 the type species (0. tenebrosus), the only one I have identified, differs 

 from those of Amblystoma in the absence of basal branchial processes, 

 and of splenial teeth. (Plates 20-21.) 



I have examined the hyoid apparatus of five species of this genus, 

 and I refer two others to it. One of these, G. cingulatus, very probably 

 belongs here ; the position of the other, G. texanus, is altogether uncer- 

 tain as yet. 



Considered with respect to the forms of their otoglossal cartilages 

 these species fall into three sections, as follows (see Plates 25 and 26): 



(1) The cartilage uninterrupted in front. G. tenebrosus, G. aterrimus, 

 and G. decorticatus. (Figs. 1, 4-5, 8-9.) 



(2) The cartilage divided in front, and without median processes. G. 

 paroticus. (Figs. 6-7.) 



(3) The cartilage divided, each half with an internal and external proc- 

 ess in front. (Figs. 1-2, PI. 26.) G. microstomus. 



In addition to these characters, it may be observed that in the 0. 

 tenebrosus and G. aterrimus there is a sheet of strong fibrous tissue 

 extending anteriorly from the otoglossal cartilage, and forming the 

 base of the tongue. A few similar fibers are found in the correspond- 

 ing position in the A. 'paroticum. 



Besides the characters of the otoglossal cartilage I have already 

 given, I may add that in the species with entire anterior border, the crest 

 of the superior surface of the basibranchial appears to pass through a 



