THE BATRACIIIA OF NORTH AMERICA. 325 



Tougae broad, obovate, sometimes nearly ovate, distinctly to not emar- 

 ginate posteriorl3\ Vomerine teeth in two ovate patches between the 

 interior nares, as near them as to each other. 



The end of the fore-arm extended reaches the external nares. The 

 heel of the extended hind leg reaches to or beyond the end of the muz- 

 zle. Two large metacarpal tubercles. Length of head to tympanum, 

 one-third that of head and body. 



Average size: Length of body, 12 lines; from vent to outer end of 

 femur, 6 lines; tibia, 7 lines; tarsus and foot, 9 lines. 



Typical coloration : Above, brown or gray, with a blackish triangu- 

 lar patch between the eyes, the apex directed backwards; the bor- 

 ders of this are of a light color, which is light green in life, and is con- 

 tinued as a band to the end of the body. Three dark bars on the lip, 

 one from the eye to the anterior ur-per arm across the angle of the 

 mouth, pale bordered above. A dark bar from the orbit across the 

 tympanum, and one from scapular region to beyond middle of side. A 

 dark bar from behind the scapular region restricts the dorsal line near 

 the sacrum, and is usually continued with an interruption to the groin. 

 Color of upper surfaces continued on a less part of surface of femur, 

 which is cross-barred; behind this pale, with a longitudinal bander 

 series of spots posteriorly. Throat in spring yellow. 



This species possesses the power of metachrosis or color-change in a 

 high degree. The dorsal stripe and border of the interocular spot may 

 be bright green, dirty white, or bright rusty ; and the dorsal tnbercles 

 vary in color in the same way. The general tint varies from bright 

 green to dull slate color. 



In its habits the Acris grylhis is a lover of the muddy borders of the 

 water, into which it leaps when alarmed. As it does not conceal itself 

 among vegetation, like the Hyla piclceringii, it is much more easily 

 caught than that species, and is more common in museums, though not 

 less abundant. As the structure of the feet indicate, it is a good swim- 

 mer, and its powers of leaping are remarkable. 



This species is distributed from Florida to Texas, through Kansas 

 and the iSTorthwest to the Atlantic, and as far northeastwardly as New 

 York. 



The northern and southern sections of this area produce forms which 

 ofter considerable differences, but which must be termed subspecies, on 

 account of the existence in some localities of intermediate individuals. 

 I have seen such from Illinois, Pennsylvania, Missouri, and elsewhere. 



These subspecies are as follows: 



Hinder foot less tarsas less than half the length of the head and body ; dermal tuber- 

 cles larger ; iiosterior femoral stripe less distinct 4 9- crepitans. 



Hinder foot less tarsus longer than half head and body; dermal tubercles smaller; 

 femoral stripe very distinct ^-i/- gryilus. 



These subspecies are respectively of northern and southern distribu- 

 tion; the A. g. gryilus ranging from North Carolina to Florida and 

 Louisiana. 



