BOTANY OP LAKE HURON. 473 



distribution tlirougliout the Province. Further south, however, 

 along the valley of the Riviere aux Sables, exist what are called the 

 sandy j)^cdns of Bosanquet, composed of a white shifting sand, 

 which, towards the coast, has been thrown up by the action of the 

 wind into parallel dunes, rising in some instances to the height of 140 

 feet above the level of the plain, and resembling ordinary i-idges of 

 hill, formed by the usual process of denudation. Southward from the 

 Aux Sables the steej) clay terraces, which to the northward are 

 observed overlooking the lake, keep gradually receding from the 

 coast-line, until within the vicinity of Sarnia, on the St. Clair, where 

 the clay again makes its appearance, and continues thence southward 

 to Lake Erie. The area between this ancient lake-margin and the 

 present beach is everywhere covered by diifting sands, similar to 

 those of the Bosanquet plains of the Aux Sables. A sand-area of a 

 somewhat analogous nature is traceable northward from Clark Point 

 to the mouth of the Saugeen River, a distance of abovit 35 miles, and 

 is found to occupy another portion of the former eastward extension 

 of the waters of Lake Huron. 



No portion of this district, however desert in repute and in fact, is 

 destitute of a certain amount of vegetation. The ceaseless motion of 

 the sand precludes the possibility of a grassy, green sward, and favours 

 only a scattered growth of perennials, springing from thick and 

 usually deep-seated roots or root-stocks, which, under the partial pro- 

 tection afforded by the scrubby growth of the oak and pine, are able 

 to maintain a sturdy growth till comparatively late in the season. 

 The more generally predominant species are here enumerated : — 



Helianthus divaricatus. Quercus ilicifolia. 



H. strumosus. Pinus resinosa. 



Helianthemum Canadense, P. Strobus. 



Liatris cylindicsea. JuDJperus Sabina, vas. procumbeus. 



L. scariosa. Pruims piimila. 



Aster multiflorus, Lithospermum birtum. 



A. undulatus. Asclepias tuberosa. 



A. azurevis. Euphorbia corollata. 



A. cordifolius. Latbyrus maritimus. 



A. ptarmicoides. Solidago bicolor. 



Quercus alba. S. memoralis 



Q. rubra. S. arguta. 



This vegetation, characterized as it is by a monotonous sameness 

 of aspect, may be considered as affording a fair, though by no means 



