CATALOG OF PLANTS. 71 



covering the ground, and a variety, the bhick blueberry, is very common 

 on flat sandy land and dunes, producing a great abundance of delicious 

 fruit. Ceanothus ovatus, C. americanns, sand cherry, bearberry and 

 Gaultheria procumbens, are plentiful in places, and all these are efficient 

 in holding the sand in place, The beautiful Cyripedium acaule is 

 plentiful near Caseville in sandy ground on the sides of and between 

 dunes. Linaria canadensis, a small blue-flowered plant, is abundant 

 throughout the sand region, and Deschampsia flexuosa freciuents 

 Klymus canadensis and Agropyron dasystachyum, good sand binders, 

 are common on the shoreward dunes near Port Austin and occasional, 

 throughout. Many other very efficient sand binders are frequent and 

 abundant in places, like Asclepias syriaca in sand near Port Aubtin, 

 also Cornus stolonifera and C. haileyi. Sweet fern, Lithospermum 

 gmelini, Lilium philadelphicum andinum, Andropogon scoperius, Koe- 

 leria cristata, Arahis lyrata, Danthonia spicata, Smilacina stellata and 

 Indian grass are scattered throughout. 



GEOGRAPHIC NOTES. 



There are no species limited or peculiar to this region, the area being 

 too small. But many other species, like the two pines above men- 

 tioned, find their limits along or near this sand dune district, some 

 reaching from the north to this line or just below it, others from the 

 south just reaching it or going very little beyond. The balsam fir 

 and sweet gale are not known farther south. Linaria canadensis is 

 occasionally noticed south of this line, and black spruce and hemlock 

 freciuently creep down as far south as Port Huron and perhaps some- 

 what farther. On the other hand, a few species common farther south 

 are scantily represented in this district. Only a few small specimen.^ of 

 sassafras were seen, and on Little Charity Island a dozen trees and many 

 shrubs of Celtis occidentalis. The tulip tree and black walnut were 

 not noticed growing Avild. although reported as ocoasionally found 

 near Sebewaing. Carya microcarpa was noted near this last place. 

 The hickories and oaks, except red oak. become less and less frequent 

 north of this line. 



A (• K XO W L E DG \i E XTS . 



Both in the field and subsequently in working up the material, I 

 became indebted to several persons for assistance. It was impossible 

 in 1908 to spend the entire summer in the field so that the special 

 effort made by every man in the part}- to gather material and data 

 on the flora was very welcome. I am also indebted to ^fr. Charles 

 McDonald, the lighthouse keeper on Charity Island, for much assist- 



