44 



SELAGINELLACEAE. 



Family 10. SELAGINELLACEAE Underw. Native Ferns 103. 1881. 



Terrestrial, annual or perennial, moss-like plants with branching stems and 

 scale-like leaves, which are many-ranked and uniform, or 4-ranked and of two- 

 types spreading in two planes. Sporanges i -celled, solitary in the axils of 

 leaves which are so arranged as to form more or less quadrangular spikes, some 

 containing 4 macrospores (macrosporanges), others containing numerous mi- 

 crospores (microsporanges), which develop into small prothallia, those from 

 the macrospores bearing archegones, those from the microspores antherids. 



The family consists of the following genus : 



i. SELAGINELLA Beauv. Prodr. Aetheog. 101. 1805. 

 Characters of family. [Name diminutive of Selago, an ancient name of some Lycopodium.~\ 



About 335 species of very wide geographic distribution, most abundant and largest in tropical 

 regions. In addition to the following some 5 others occur in western North America. 

 Stem-leaves all alike, many-ranked. 



Stems compact with rigid leaves; spikes quadrangular. i. S. rupestris. 



Stems slender; leaves lax, spreading; spikes enlarged,^carcely quadrangular. 2. 5. selaginoid.es, 

 Stem-leaves of 2 kinds, 4-ranked, spreading in 2 planes. 3. S. apus. 



i. Selaginella rupestris (I,.) Spring, 

 Rock Selaginella. (Fig. 99.) 



Lycopodium ru pest re L. Sp. PI. noi. 1753. 

 Selaginella rupeslris Spring in Mart. Fl. Bras, 

 i: Part 2, 118. 1840. 



Stems densely tufted, with occasional 

 sterile runners and sub-pinnate branches, 

 i '-3' high, commonly curved when dry. 

 Leaves rigid, appressed-imbricated, i" or 

 less long, linear or linear-lanceolate, convex 

 on the back, more or less ciliate, many-ranked, 

 tipped with a distinct transparent awn ; 

 spikes sessile at the ends of the stem or 

 branches, strongly quadrangular, 6"-i2 /r 

 long, about i" thick; bracts ovate-lanceo- 

 late, acute or acuminate, broader than the 

 leaves of the stem ; macrosporanges and mic- 

 rosporanges borne in the same spikes, the 

 former more abundant. 



On dry rocks, throughout the northern hem- 

 isphere, and in Africa. Ascends to at least 

 2000 ft. in Virginia. Aug. -Oct. 



2. Selaginella selaginoides (I,.) 

 Link. Low Selaginella. (Fig. 100.) 



Lycopodium selaginoides L. Sp. PI. noi. 1753. 

 Sclaginella spinosa Beauv. Prodr. Aetheog. 112. 

 1805. 



Selaginella selaginoides Link, Fil. Hort. Berol. 

 158. 1841. 



Sterile branches prostrate-creeping, slen- 

 der, Yt'-'i' long, the fertile erect or ascend- 

 ing, thicker, i/-3' high, simple; leaves 

 lanceolate, acute, lax and spreading, sparsely 

 spinulosc-ciliate, x'^'^long ; spikes solitary 

 at the ends of the fertile branches, enlarged, 

 oblong-linear, subacute, i' or less long, 

 2"-2%" thick ; bracts of the spike lax, as- 

 cending, lanceolate or ovate-lanceolate, 

 strongly ciliate. 



< Hi wet rocks, Labrador to Alaska, south to 

 >ew Hampshire. Michigan and Colorado. Also 

 in northern Europe and Asia. Summer. 



