MICHIGAN ACADEMY OF SCIENCE. 169 



Ribes vulgare Lam. Red Currant. — Occasional as an escape from cultiva- 

 tion. Noticed often along fences and on borders of woods, also on Walpole 

 Island. 



Ribes triste Pall. Swamp Red Currant. — Frequent in damp rich woods 

 and tamarack swamps. 



Ribes aureum Pursh. Buffalo Currant. — Occasional as an escape from 

 cultivation to fences and roadsides. Abundant and spreading in sand at 

 Point Edward. 



Hamamelidaceae. Witch-hazel Family. 



Hamamelis virginiana L. Witch-hazel. — Abundant in damp open woods 

 or in poor and dry open ground. 



Platanaceae. Plane Tree Family. 



Platanus occidentalis L. Sycamore. Buttonwood. — Frequent in rich 

 ground, especially along streams and on river bottoms. 



Rosaceae. Rose Family. 



Physocarpus opulifolius (L.) Maxim. Nine-bark. — Frequent in damp 

 open thickets and along the banks of streams. 



Spiraea salicifolia L. Meadow-sweet. — Common in low ground, on 

 borders of marshes and around ponds. 



Sorbaria sorbifolia (L.) A. Br. Mountain Ash Spiraea. — Occasionally^ 

 found as an escape in towns and villages. 



Pyrus communis L. Common Pear. — Inclined to escape and remain in a 

 few places. 



Pyrus baccata L. Siberian Crab. — Occasionally found as an escape to the 

 bank of St. Clair River on the Indian Reservation south of Sarnia. 



Pyrus coronaria L. American Crab. — Ver}' common in open woods, 

 thickets, and on dry banks of streams. 



Pyrus mains L. Apple. — Frequent as an escape in open woods, thickets, 

 and along streams. Abundant on the Indian reservations. A very large 

 tree, probably set out by missionaries, a Rhode Island greening, noticed on 

 Ste. Anne's Island, over two and one-half feet in diameter two feet from 

 ground. 



Pyrus arbutifolia atropurpurea (Britton) Robinson. Cliokeberry. — Fre- 

 quent among other shrubs in swampy places. 



Pyrus melanocarpa (Michx.) Willd. Black Chokeberry. — Often very 

 common in damp and swampy places. 



Pyrus americana (Marsh.) DC. American Mountain Ash. — Planted for 

 ornament and inclined to escape. Several small trees, apparently native, 

 on top of Gilnockie, one of the highest sand dunes at Port Franks. This 

 may be the form described fiy Prof. C. S. Sargent under name of Sorbus 

 Americana decora. Sarg. 



Amelanchier canadensis (L.) Medic. Shad Bush. Juneberry. — Common 

 on dryish ground in open woods and thickets. Often a tree eight inches in 

 diameter and 60 feet high. 



Amelanchier oblongifolia (T. and G.) Roem. Service Berry. — Frequent in 

 dry and sandy ground, especially on sand dunes bordering Lake Huron 

 shore. 



