110 PEOCEEDINGS OF THE ACADEMY OP 



differeut in proportions from Plethodon intermedius, but with a broader 

 and more flattened head. 



The head is an elongate oval, slightly truncate in front; the nostrils are 

 antero-lateral, and with a delicate groove connecting with the commissure 

 of the mouth. Canthus rostralis not marked. The muzzle is aa long as the 

 fissure of the eye, while the length of the commissure of the mouth (diagonal 

 line) is equal to the width of the head at the rictus. The tongue is largely 

 free, the posterior portion rather narrowly. The inner nares are nearer to- 

 gether than the outer. The vomerine teeth commence behind the nares and 

 form a single series of eight on a ridge, which is gently arched backwards 

 on the median line. The parasphenoid patch does not extend quite forwards 

 to the middle of the orbits ; it is much flatter and wider anteriorly than in 

 A. lugubris, and contains opposite the posterior margin of the orbits 

 ten longitudinal series of teeth, those of adjacent rows alternating. 



Gular fold well marked ; costal folds fourteen, not continued on back or 

 abdomen. The limbs, and especially the digits, are slender ; appressed to the 

 side they fail to meet by the length of the fingers. The form of the body is 

 slender and cylindric, and the width of the head enters the total length of 

 the groin seven times. The tail is as in A. lugubris, equal to the head 

 and body in length, cylindrical, slender, and slightly compressed at tip. 



The thumb possesses a short phalange, but no part of it is free as in A. 

 lugubris; on the other hand, all the phalanges of the other toes of both 

 feet are more slender than the A. 1 u g u b r i s, and the distal ones distinctly 

 truncate and slightly emarginate, with dermal thickening below tip. All are 

 quite free. Number of phlanges 1 — 2—3—2, 1 — 2—3—3 — 2. 



Coloration. — Sides and nape greenish gray; top of head and dorsal region 

 behind in the form of a serrate band, with the tail black ; below yellowish 

 brown. Limbs black above, brown below. Inferior regions unspotted. 



Measurements. 



Inch. 



Length (axial) from snout to rictus oris -42 



" " axilla •TO 



" " groin l-VS 



" " end vent 2 



" " end tail 3-65 



fore limb -5 



" foot -2 



hind limb -55 



" foot. -26 



Width " " (sole) -11 



head at rictus oris "28 



body at middle -24 



" " sacrum -2 



The maxillary bone displays the same sudden decurvature anterior to and 

 below the orbit which the A. lugubris does, but it is less marked ; in conse- 

 quence the commissure of the mouth is less sinuate. The long mandibular 

 and maxillary teeth, while of similar structure, are less developed ; perhaps 

 larger specimens of this species may be found where they may be larger, as 

 in small specimens of A. 1 u gub r i s, they are nearly similar in propor- 

 tions. 



Though nearly allied to the A. 1 ugu b r i s, the present species will never 

 be confounded with it. It is a much weaker form, and does not display the 

 characters of the genus in so striking a degree. But one specimen has come 

 under my observation, as follows: 



No. 6794; one specimen ; Fort Umpqua, Oregon, Dr. Vollea. 



TIIORIID.E. 

 Palatines not prolonged over parasphenoid bone; no postorbital arch. 



[May, 



