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and nowhere else in the State. They occur for the most part in and 
around the borders of the Tamarack marshes, which are familiar features 
in many of the counties in this area of Indiana. Numerous other species 
whose range is given by Le Conte and Horn as “southern border of British 
America and northern United States” occur in this Transition Zone of the 
State, and a complete list of them will be given in the paper on Coleoptera 
when published. 
THE LOWER AUSTRAL ZONE. 
The extreme northern boundary of the Lower Austral life zone passes 
in a northwest-southeast direction through the following counties in In- 
diana: Vigo, Clay, Owen. Monroe, Jackson, Jennings, Jefferson and 
Switzerland. In the territory south of this line the Austroriparian fauna 
of that zone overlaps and merges with the Carolinian fauna of the Upper 
Austral zone. The extension northward on the western line of the State 
is, without doubt, due to the presence of the broad and sheltering valley 
of the Wabash River, within the confines of which certain southern forms 
have found a climate mild and suitable to their habits. Within this val- 
ley the following members of the Austroriparian flora grow indigenously, 
a number of them as far north as Terre Haute: Bald cypress, T’arodium 
distichum (.); upright burhead, Pchinodorus cordifolius (1.) 3; showy 
amaryllis, Hymenocallis occidentalis (LeC.); pecan, Hicoria pecan 
(Marsh); swamp or downy poplar, Populus heterophylla L.; chinquapin, 
Castanea pumila (.); Texan red oak, Quercus teruna Buckley ; pipe vine, 
Aristolochia tomentosa Sims; American lotus, Nelumbo lutea (Willd.) ; 
Carolina moonseed, Cebatha carolina (.); great burnet, Sanguisorba 
canadensis Iu.; water or swamp locust, Gleditsia aquatica Marsh; water 
ash, Fraxrinus caroliniana Mill, and crossvine, Bignonia erucigera L. 
Among other characteristic southern plant forms occurring in Indiana 
south of the northern boundary of the Lower Austral zone are: The 
yellow pine, Pinus echinata Mill.; mud plantain, //eteranthera reniformis 
R. & P.; false aloe, Agave virginica L.; Spanish oak, Quercus digitata 
(Marsh); southern hackberry, Celtis mississippiensis Bose.; American 
mistletoe, Phoradendron flavescens (Pursh.); cucumber tree, Alagnolia 
acuminata I..; pencil flower, Stylosanthes biflora (.) ; Carolina buckthorn. 
Rhamnus caroliniana Walt.; yellow passion flower, Passiflora lutea 1.; 
Hercules club, Aralia spinosa L.; persimmon, Diospyros virginiana L.; uni- 
corn plant, Martynia lowisiana Mill.; catalpa, Catalpa catalpa (1), and 
the rough button-weed, Diodia teres Walt. 
