PHILOSOPHICAL SOCIETY OF WASHINGTON. 87 



Salix longifolia has this year (1881,) flowered twice ; once in April 

 and again in June. 



Autumnal blooming, in so far as it is peculiar to this climate, 

 may be chiefly attributed to the tolerably regular occurrence here 

 of a hot and dry season in midsummer. This usually begins 

 towards the end of June and ends about the middle of August. 

 During this period, in some seasons, the ground and vegetation 

 become parched and dried up, so that vegetal processes in many 

 plants cease almost as completely as in the opposite season of cold. 

 From this dormant state, the warm and often copious rains of the 

 latter part of August revive them, as do the showers of spring, and 

 they begin anew their regular course of changes. The frosts of 

 October usually cut their career short before maturity is reached, 

 but in some cases two crops of seed are produced. In addition to 

 this, there frequently also occurs a very warm term in November, 

 often extending far into December, and of this certain species take 

 advantage and push forth their buds and flowers. 



Albinos. 



Well defined albinos have been collected of the following species 



Desmodium nudiflorum. 

 Liatris graminifolia. 

 Rhododendron nudiflorum. 

 Vinca minor. 

 Mertensia Virgin ica. 

 Sabbatia angularis. . 

 Pontederia cordata. 



The green flowered variety of Trillium sessile is also common, 

 and Gonolobus obliquus exhibits on High Island this same anom- 

 alous feature. Carez tentaculata having the spikes perfectly white, 

 as if etiolated, was found June 14 of this year, (1881,) on the East- 

 ern Branch marsh. This last phenomenon was certainly due 

 neither to maturity or disease, but was a mere lusus naturae. 



Double Flowers, &e. 



Thalictrum anemonoides, Ranunculus bullosus, Claytonia Virgin- 

 ica, and Rubrus Canadensis, have been found with the flowers much 

 doubled as in cultivation. 



