212 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. [1885. 



behind the symphysis of the lower jaw are indications of a bright yel- 

 low spot. The upper half of the tail is not so dark as the back, the lower 

 half duskier than the belly. The limbs below and in front yellowish, as 

 other lower parts. Feet, especially above, dark. This species must be 

 (iompared with A. hicolor, A. tigrinum, and possibly with A. ohscurum. 

 Tbe last two belong to the group which has twelve costal grooves, as the 

 si)ecies are arranged in Prof. E. D. Cope's ''Review of the Amblystom- 

 idie" (Proc. Acad. Nat. Sci. Phila., 1867, 166). A. ohscurum has the 

 internal nares no more widely separated than are the outer; the limbs 

 of the palatine V are decidedly concave, and the inner series of teeth 

 are about twice the length of the outer. The frontal region of A. oh- 

 scurum is also said to be very convex. It is also a rather long-bodied 

 species, the distance from the snout to the axilla being contained in the 

 distance from the snout to the [groin] nearly two and four-tenths times, 

 while in A. copeianum the latter distance is but twice the former. In- 

 deed, this form difters from all others, so far as my knowledge extends, 

 in this equality of the distances from snout to axilla and from axilla to 

 groin. A. hicolor approaches it most nearly. In such specimens of A. 

 tigrinum as I have been permitted to examine, the ratio of the two 

 dimensions is about the same as given above for A. ohscurum. It is 

 about the same in specimens of A. mavortium, as deduced from meas- 

 urements g-iven in Professor Coi^e's paper cited above. From A. tigrinum 

 my species difters further in having no traces of the yellow spots so 

 characteristic of that common form. A. copeianum has also a broader 

 and more depressed head, a more compressed tail, and longer limbs. 



A. hicolor is described as having the palatine teeth in three entirely 

 transverse series; as having a very short muzzle, and as being more or 

 less spotted. A comparison of some of the dimensions of the two spe- 

 cies is necessary. The type of A. hicolor now in the museum of the 

 Academy of the Natural Sciences of Philadelphia furnishes the meas- 

 urements found in the first column, which are taken principally from 

 Professor Cope's paper. Those marked with an asterisk have been 

 kindly obtained for me by Prof. Angelo Heilprin. It is almost exactly 

 the size of the type oi A. copeianum, 5 inches 10.05 lines. 



Measurements. 



A. copelan- 

 nm. 



Longth from snout to gular fold 



Lenjith from snout to axilla 



Lpngtli from snout to "Toin 



Leusth from sTiout to end of vent 



Length axilla to groin 



Length lower leg and foot 



Width of head 



Fore-arm and foot into (Hslante snout to groin.. 

 Lower leg and foot into distance snout to groin.. 

 Whole anterior limb into distance snout to groin 

 Whole anterior limb into distance snout to vent , 



In. Lin. 

 8.5 



1 1.8 



2 3 



3 



1 1.15 

 9 

 7.5 



limes. 

 3.6 

 3 



2t\ 

 3A 



