Selaginella. SELAGINELLE^E. 349 



ORDER LYCOPODIACE^E, the Club-Moss or Ground-Pine Family, is character- 

 ized by the small leaves, usually lanceolate or subulate, sometimes oblong or round- 

 ish, not divided, persistent, placed in 2 to many rows on trailing or sometimes erect 

 usually branching stems, and by the 1 - 3-celled sporangia solitary in the axils of the 

 leaves or on their upper surface, all filled with numerous minute spores, and sepa- 

 rating into 2 or 3 valves when mature. Prothallus [in the only known instance] 

 underground and without chlorophyll. 



An order of three genera, Lycopodium, Tmesipteris and Psilotum, the latter of very few species, 

 the first numbering about 100, of which 11 are found in North America. The genus LYCOPODIUM, 

 Linn., consists of moss-like plants, with leaves varying from round to slenderly subulate and 

 imbricated in 4 to many rows on the pinnately or dichotomously branching stems, and with reni- 

 form 1 -celled sporangia opening transversely, situated in the axils of the ordinary leaves, or the 

 fruiting leaves modified into bracts and the fructification forming stalked or sessile spikes. No 

 species is known to have been as yet found in California, but the following may be looked for on 

 the mountains of the northern part of the State. Both have distinct spikes of fructification. 



L. ANNOTINUM, Linn. Stems creeping ; branches upright, dichotomous, 4 to 6 inches high : 

 leaves in several ranks, spreading, lanceolate, pointed, serrulate, 2 to 4 lines long : spikes solitary 

 at the ends of leafy branches. Washington Territory, northward to Unalaska and eastward to 

 the Atlantic. 



L. CLAVATUM, Linn. Stems widely creeping ; branches upright, subpinnately branched, 4 to 8 

 inches high : leaves many-ranked, linear-subulate, spreading, but with the apex incurved and 

 bristle-pointed : spikes 2 to 4 together on a slender terminal peduncle. Same range as the last. 



TMESIPTEUIS FORSTERI, Endlicher, an Australasian plant, nearly a foot high, with vertical 

 oblong leaves half an inch long, some of them 2-lobed and bearing in the fork a large 2-celled 

 sporangium, is accredited to California in Bot. Beechey, and there are specimens at Kew marked 

 "California, Douglas" ; but there is no recent evidence that it is a Californian plant. 



DIVISION II. HETEROSPOROUS VASCULAR ACROGEXS. 



Plant producing two kinds of spores ; the larger ones (macrospores) developing a 

 prothallus with archegonia ; the smaller ones (microspores) producing antherozoids. 



ORDER CXXIII. SELAGINELLE^S. 



Leafy plants, terrestrial or rooted in mud, never of great size ; the stems branching 

 or corm-like, and the leaves minute and arranged in four rows or subulate and 

 elongated. Sporangia one-celled, solitary, axillary or borne on the upper surface of 

 the leaf near its base and enwrapped by its margins, some containing macrospores 

 only and others only microspores. 



1. SELAGINELLA, BEAUVOIS. 



Sporangia axillary, minute, subglobose, opening transversely ; some containing 

 usually 4 globose macrospores, others, which are smaller and more abundant, filled 

 with numerous microspores. Moss-like plants with slender branching stems and 

 small leaves arranged in 4 or several ranks. 



The number of species described is over 200, the greater part tropical. Many of them are very 

 elegant, and a few are common in conservatories. 



* Leaves all alike, arranged in many ranks, those of the fruiting spikes ^-ranked, 



but otherwise like the rest. 



1. S. rupestris, Spring. Stems prostrate or ascending, rather rigid, 2 to 12 

 inches long, vaguely or subpinnately branching : leaves glaucescent, closely irnbri- 



