KEYS FOR THE IDENTIFICATION OF NORTH 

 AMERICAN SALIENTIA 1 



(For terms used in Keys, refer to Fig. 12. For method of using Keys, see 

 footnote 2.) 



PRELIMINARY KEY TO FAMILIES 



(See page 7 for internal characters determining classification into Families.) 

 I. Pupil of eye vertical. 



A. Inner sole tubercle small; ear not visible; parotoid glands present; size 



small. Northwestern United States (Washington). 



Ascaphus, of the Family' Discoglossidce. (See p. 51.) 



B. Inner sole tubercle large, with extensive cutting edge. 



PelobatidcB. (See First Key, p. 43.) 

 II. Pupil not vertical; either horizontal or round. 



A. Parotoid glands always present. 



BujonidcB. (See Second Key, p. 44.) 



B. Parotoid glands lacking. 



1 . Fingers and toes more or less enlarged at tips, to form adhesive disks. 



a. Disks T-shaped, small; undersurface of frog smooth. 



Cystignathidce. (See Third Key, p. 45.) 



b. Disks round, large or small; undersurface more or less granulated. 



Hylida. (See Fourth Key, p. 46.) 



2. Fingers and toes without disks. 



a. Head narrow and mouth small; a fold of skin on top of head behind 



eyes; ear not visible; size small (ij inches, or less). 



Engystomatidce. See Fifth Key, p. 48.) 



b. Head not unusually narrow; mouth large; ear distinct; size 2 inches 



or more (except in immature). 



Rvnidce. (See Sixth Key, p. 48.) 



FIRST KEY. SPECIES OF PELOBATID.E (Spadejoot Toads) 



I. Ear distinct; parotoids round, flat; black granulations on top of head; two 

 curved yellowish lines on back. Eastern North America. 



Scaphiopus holbrookii. (See Colour Plate II, also p. 53.) 



1 These keys are more or less artificial. Unfortunately, they cannot be based on colour, because 

 of the great variation and the lack of stability in both colour and colour pattern in the members of 

 this order. Also, it has been impossible to avoid detail and combine brevity with definiteness, be- 

 cause of the similarity of the various species. 



2 Method oj using Keys. As long as the specimen agrees with the characteristics named in the 

 Key, read continuously until a technical name is designated at the extreme right. As soon as the 

 specimen disagrees with the Key characteristics, skip from the point of disagreement to the num- 

 ber or letter next in order. 



In all instances where size is not mentioned, medium size (about 3 inches) is understood. 



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