52 Bicknell : Ferns and flowering plants of Nantucket 



Britton's 0. arenarium but are nevertheless unmistakably 0. 



vulgatum. 



led by Mrs. Owen from Polpis and Sachacha Pond, 

 1885 and 1886. 



BOTRYCHIUM OBLIQUUM Muhl. 



' Occasional, usually single plants or a few together. Below 

 the " cliff" in white sand with Ibidium Beckii and Lechea maritima; 

 west of the town ; Shawkemo ; Quaise ; Polpis; Squam. Some- 

 times under 10 cm. high with leaves only 3-4 cm. wide; largest 

 examples 29 cm. high ; ultimate segments of the leaves numerous 

 and crowded, the stalks and their divisions bearing pilose hairs. 



Recorded by Mrs. Owen from one station at the south shore 

 in i860 and from west of the town in 1885. 



OSMUNDACEAE 



OSMUNDA SPECTABILIS Willd. 



Uncommon. Below the u cliff"; south and west of the town ; 

 Monomoy ; Polpis ; Squam. 



OSMUNDA CINNAMOMEA L. 



Low grounds everywhere ; perhaps the most common fern of 

 the island. 



Osmunda Clayton 1 ana L. 



Nothing was seen of this fern. The catalogue reports a single 

 specimen from near Sachacha on the joint authority of Mrs. 

 Owen and Mr. Dame. 



POLYPODIACEAE 

 Pteridium aquilinum (L.) Kuhn. 



Common throughout ; of large size in low thickets at Polpis 

 and Squam. 



* Pteridium aquilinum latiusculum (Desv.) Underw. 



Common. Much of the brake fern of the island is a form ap- 

 pearing more or less intermediate between aquilinum and latiuscu- 

 lum, but examples fully representative of the latter are common. 



Lorinseria areolata (L.) Underw. 



Locally common, especially on the eastern side of the island. 



