Eaton : Pteridophytes 



485 



Psilotum nudum (L.) Griseb. 



Not uncommon in decaying vegetable matter, often at the 

 bases of palmetto trees. It grows most luxuriantly in decayed 

 places in prostrate logs or living trees, sometimes at an altitude 

 of 5 meters. Some specimens obtained at Costello's hammock 

 are 4.5 dm. high and 3 dm. broad. 



Selaginella rhodospora Baker* 



Apodae. Tufts small ; plant annual, pinnate, 1—3 cm. long ; 

 branches short, 2 mm. broad ; under leaves spaced or slightly 

 imbricated, 1.75-2 mm. long by 0.75 mm. broad, obliquely ob- 

 long, the upper edge more rounded, apiculate, finely papillose 

 over the upper surface, each margin with 14-18 minute bristle- 

 like teeth ; upper leaves lanceolate, long acuminate, appressed to 

 the stem, 1 mm. long, 0.25 mm. broad, with about 7 setae on 

 each -side ; spikes 2-5 mm. long; sporophyls 1.6 mm. by 0.57 

 mm., ovate-lanceolate, abruptly long-acuminate and ending in a 

 rough awnlike point, the edges slightly hyaline and with 15-18 

 bristles, the under ones broader, divaricate and fructiferous, the 

 upper darker green and sterile, keeled and bristled on the back to- 

 wards the apex ; gynospores reddish-orange, 22 /i in diameter, 

 coarsely tubercled ; androspores not seen. 



A very delicate little species growing among the algae on the 

 borders of pot-holes on the edges of the prairies, where inundated 

 most of the year. Black Point bridge and beside a prairie below 

 Homestead, in November and December. Evidently only col- 

 lected once before, in eastern Cuba, by Wright. This has been 

 erroneously referred by Gilbert * to S. caribensis Jenman. 



Selaginella arenicola Underw. 



Common in the sandy pine woods about Alapattah, but appar- 

 ently absent from the rocky woods from Miami southward. 



ISOETACEAE 



Isoetes flaccida Shuttlew. 



Rich soil, border of everglade at Orange Glade, border of the 

 north fork of the Miami at the rapids, and in the brook at Snapper 



*Fern Bull. 13 : 74. 



