Distribution 



(Norfolk, Virginia), and those states bordering the Gulf of Mex- 

 ico, Georgia, Florida, Alabama, Mississippi, Louisiana, and the 

 eastern one-third of Texas. It also contains the country along 

 the Mississippi to southern Illinois. West of the Mississippi, its 

 boundary line extends southward from Missouri to the mouth of 

 the Rio Grande in Texas. 



This subregion has a large number of toads and frogs. It 

 is the richest of all the subregions in members of the Hylidae. Its 

 forest areas and many streams, its relatively high temperature 

 and humid air, make it peculiarly well adapted to the needs of 

 this group. The subregion has many species peculiar to it ; namely, 

 Hyla cinerea, Hyla squirella, Hyla gratiosa, Hyla femoralis, 

 Choropbilus ornatus, Choropbilus ocularis, Chorophilus occidentalis, 

 Engystoma carolinense, Bufo quercicus, Bufo lentiginosm, Rana 

 grylio, Rana asopus, and Rana spbenocepbala. Of these species 

 peculiar to the subregion, many are found in the eastern sec- 

 tions and Texas as well, but Bufo quercicus and Rana grylio are 

 not found west of the Mississippi and Hyla gratiosa and Rana 

 cesopus are not found outside of Florida. Peninsular Florida is a 

 faunal region distinct from the Austroriparian, but the evidence 

 of this does not rest largely in the distribution of the Salientia. 

 Florida has a member of the Cystignathidae (Litbodytes ricordii), 

 a wanderer from the West Indies. 



The Austroriparian overlaps the Sonoran subregion in Texas. 

 The species that it gains from the Sonoran in this overlapping 

 are either toads or members of the Cystignathidse adapted to 

 live in rocky ravines or among limestone cliffs. They are the 

 following: Bujo compactilis, Bufo debilis, Bufo valliceps, Bufo 

 punctatus, Bufo I. woodbousei, Litbodytes latrans, and Syrrophus 

 marnockii. This subregion, though itself poor in toads, gets so 

 many additions from the two adjacent subregions that it makes 

 a showing of seven species, possessed mainly by Texas, of 

 course. 



The Sonoran subregion is made up of the Upper and Lower 

 Austral zones from the Western plains inclusive to the Pacific 

 Coast. At the south it includes Lower California, Arizona, New 

 Mexico, and western Texas, as well as the northwestern part of 

 Mexico. At the north it extends into Montana east of the Rocky 

 Mountains, to British Columbia between the Rocky Mountains 

 and the Sierra Nevadas, and not quite as far north as Oregon west 



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