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and nowhere else in the Slate. 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, Taxodium 

 distickum (L.) ; upright burhead, Echinodorus cordifolius (L.) ; showy 

 amaryllis, Hymenocallis occidentalis (LeC.) ; pecan, Hicoria pecan 

 (Marsh); swamp or downy poplar, Populus heterophylla L. ; chinquapin, 

 Castanea pumila (L. ) ; Texan red oak, Quercus texana Buckley; pipe vine, 

 Aristolochia tomentosa Sims; American lotus, 'Nelumbo Jutea (Willd.) ; 

 Carolina moonseed, Oebatha Carolina, (L.) ; great burnet, Sanguisorua 

 canadensis L. ; water or swamp locust, Gleditsia aquatica Marsh ; water 

 ash, Fraxinus caroliniana Mill, and crossvine, Bignonia crucigera 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, Jleteranthera reniformis 

 R. & P.; false aloe, Agave virginica L. ; Spanish oak. Quercus digitata, 

 (Marsh); southern hackberry, Celt is mississippiensis Bosc. ; American 

 mistletoe, Phoradendron flavescens (Pursh.) ; cucumber tree, Magnolia 

 acuminata L. ; pencil flower, Htylosanthes oiflora (L.) ; Carolina buckthorn. 

 Rhamnus caroliniana Walt. ; yellow passion flower, Passiflora lutea L. ; 

 Hercules club, Aralia spinosa L. ; persimmon, Diospyros rirginiana L. ; uni- 

 corn plant, Martynia louisiana Mill.; catalpa, Catalpa catalpa (L.). and 

 the rough button-weed, Diodia teres Walt. 



