FLORA OF WASHINGTON AND VICINITY. 97 



OLEACE^ 



Olive Family. 



t Fraxinus Americana, L. White Ash. 

 First of May ; fruit in July. 



tFraxinus pubescens, Lam. Red Ash. 



Last of April ; fruit iu July. 



Fraxinus viridis, Miclix. f. Green Ash. 

 A^iril; fruit, June or July. 



t Chionanthua Virginica, L. Fringe-Tree. 



Leaves fragrant iu drying. Last half of May. 



APOCYNACEiE. 



Dogbane Family. 



Vinca j/iiHor, L. Periwinkle. (Very improperly called Myrtle.) 



Frequently with pure white flowers. Escaped in many places. Last of April or 

 first of May. 



t Apocynum cannabinum, L. Dogbane. Indian Hemp. 

 Last half of June. 



Apocynum cannabinum, L., var. glaberrimum, DC. 



Flats at Little Falls. I retain De Caudolle's variety name, though dropped by 

 Professor Gray, because this form is here very well marked, the typical form being 

 also common. July. 



ASCLEPIADACEiE. 



Milkweed Family. ^ 



tAsclepias tuberosa, L. Butterfly- weed. Pleurisy-root. 

 July. 



t Asclepias rubra, L. 



Holmead and Terra Cotta Swamps; rare. Middle of July. 



tAsclepias purpurascens, L. Purple Milkweed. 



Not common. 



tAsclepias incarnata, L. Swamp Milkweed. 

 Last of July. 



Asclepias incarnata, L., var. pulchra, Pers. 



First of August. 



t Asclepias Cornuti, Decsne. Common Milkweed. Silkweed. 

 Last half of June. 



tAsclepias obtusifolia, Michx. 

 June. 



tAsclepias variegata, L. Variegated Milkweed. 

 Last of May to middle of June. 

 Bull. Nat. Mus. No. 22 7 



