FLORA OF WASHINGTON AND VICINITY. 139 



Aspidium marginale, Swartz. Evergreen Wood-Fern. 

 September, October. 



Aspidium spinulosum, Swartz, var. intermedium, Willd. Common Wood-Fern. 



September, October. 



t Aspidium acrostichoides, Swartz. Christmas Fern. Christmas Shield-Fern. 

 September, October. 



Cystopteris fragilis, Bernh. Britlle Fern. 

 High Islautl. July. 



t Onoclea sensibilis, L. Sensitive Fern. 

 Last of May or in June. 



Woodsia obtusa, Terr. Obtuse-leaved Woodsia. 

 Eud of May or in June. 



Dicksonia pilosiuscula, Willd. [i>. punctUohuIa, Kunze.] Hay-scented Fern. 

 Hairy Dicksonia. 

 June. 



Lygodium palmatum, Swartz. Climbing Fern. Hartford-Fern. 



Thus far found only in oue little swami) near the Sligo ; in fruit October 12, 1879. 

 This plant is annually brought into the Washington markets from some point in 

 Maryland not yet discovered by botanists. 



Osmunda regaUs, L. Royal Fern. Flowering Fern. 

 June. 



Osmunda Claytoniana, L. Clayton's Flowering Fern. 

 July. 



t Osmunda cinnamomea, L. Cinnamon Fern. 

 Last of May or first of June. 



OPHIOGLOSSACEiE. 



Adder's-Tongue Family. 

 tBotrychium ternatum, Swartz, var. obUquum, Milde. Ternate Grape-Fern. 

 September to November; found in fine condition November 16, 1873. The brown 

 fronds persist through the hardest winters. 



tBotrychium ternatum, Swartz, var. dissectum, Milde. 



September to November ; found as late as November 3, 1878. 



tBotrychium Virginianum, Swartz. Rattlesnake Grape-Fern. Virginian 

 Grape-Fern. 



Last of May or first of June. 



t Ophioglossum vulgatum, L. Common Adder's-tongue. 



Locke's Branch of Rock Creek near Blagden's Mill (Mr. J. M. Comstock, 1875); 

 Bladensburg (Professor Chickering); Back Lick Run. May. 



LYCOPODIACEiB. 



Club-Moss Family. 



tLycopodium lucidulum, Michx. Club-Moss. 



August. 



