206 THE MICHIGAN ACADEMY OF SCIENCE. 



Salicaccrr. 



Salix alba Lin. is occasional on shores of Orion Lake. 



Salix humilis Marsh, var. Keweenawensis. A low form growing 

 amongst rocks. Young leaves rotnnd, mature broadly obovate, densely 

 tomentose; resembling those of S, Nutallii Sarg. {S. flavescens Nutt.), 

 but broader, Keweenaw county. 



S. argyrocarpa Anders., a small shrub, about six inches high, with 

 oblanceolate leaves, silvery-silky underneath, was collected in Kewee- 

 naw county in 1889. It Avas found growing in the crevices of rocks on 

 bluffs. Kare. 



S. cordata Muhl. var augustata (Ph.) Anders. ^ is frequent at Detroit 

 and Yi^silanti. It is the form with narrow leaves tapering to an acutish 

 base. 



Salix pentandra Lin. near Rochester. Frequent in swamps and bears 

 fruit in September. 



Castancaccce. 



Quercus rubra Lin. var. borealis (J/,r. f.) [Quercus horeaUs Mx. f. N. 

 Amer. Syl. 1, 98, 1819; Q. amhigua Mx. f. Hist. Arb. Am. 2, 120, pi. 24, 

 1812 not Humb.). This is the northern form with the leaves of ordi- 

 nary Q. rubra and the fruit of Q. coccinea, that is, with a hemispherical 

 or turbinate cup. Common in the Upper Peninsula, where it becomes 

 an extremely large tree in the valleys or a bushy shrub or small scraggy 

 tree along rock ledges. 



Quercus acuminata var. Alexandri. A large tree 100 to 125 feet in 

 height and from two to five feet in diameter; bark gray, deeply fur- 

 rowed, one and one-half to three inches thick, leaves obovate, oblong, 

 or lanceolate, crenately toothed, the teeth with a very short, blunt 

 mucro ; thinner and more papery than in the species ; lighter green. 

 Flowering and fruiting two or three weeks later. Fruit smaller. May 

 and June, acorns ripe in November. Sweet. Edible. Once very ex- 

 tensive in Oakland county, bu^ rapidly disappearing through the de- 

 mand for it as lumber. Named in honor of the discoverer, Mr. S, Alex- 

 ander of Birmingham. Perhaps a hybrid between Q. acuminata and Q. 

 platanoides, 



Aristolochiacecc. 



Asarum reflexum Bicknell occurs at Birmingham and on Belle Isle; 

 the var, ambiguum Bickn., in Keweenaw county; A. acuminatum Bickn. 

 Is also frequent in KeAveenaw county; A. canadense Lin. occurs at 

 Detroit.' 



Aristolochia macrophylla Lam. I collected near Ypsilanti. It may 

 have been an escape from cultivation. 



Poljjgonaceo'. 



Rheum Rhaponticum Lin. The rhubarb or pie-plant is an escape from 

 cultivation in places in Keweenaw county and near Ypsilanti. 



Polygonum viviparum Lin., the Alpine Bistort, Tvitfr more or less of 

 the flowers replaced by bulblets, is occasionally found on rocky shores 

 of KeweenaAv Point, There are two forms of Polygonum amphibium Lin. 

 One is a comparatively simple plant with few branches and short-petioled 



