50 



SELAGINELLACEAE 



11. Selaginella asprella Maxon. 

 Bluish Selaginella. Fig. 109. 



Selaginella asprella Maxon, Smiths. Misc. Coll. Va-'^: 6. pi. 4. 1920. 

 Stems loosely matted, 3-6 cm. long, creeping but not 

 prostrate, rooting at intervals ; branches laxly ascending, 

 usually intricate, 1-2.5 cm. long, 2-pinnate, the divisions 

 3-7 mm. long, oblique, slender. Leaves rigidly ascending, 

 subdistant, subimbricate, 2.75-3.2 mm. long (seta included), 

 the blades narrowly deltoid-subulate, strongly glaucous, 

 whitish-marginate ; seta 0.7-0.9 mm. long, white-hyaline, 

 subflexuous, serrulate ; cilia 16-23 on each side, mostly 

 spreading, 0.05-0.09 mm. long, the upper ones shorter and 

 oblique. Spikes loosely aggregate, apical, 1-2 cm. long, 

 1.5-2 mm. thick, arcuate; sporophylls la.xly imbricate, 2.5-3 

 mm. long (seta included), the blades narrowly ovate- 

 deltoid, long-acuminate ; seta 0.6-0.8 mm. long, whitish, 

 strongly scabrous ; cilia 25-35 on each side, mostly 0.03- 

 0.06 mm. long; megaspores yellow, 0.375 mm. thick, lightly 

 reticulate ; microspores orange, about 0.033 mm. thick. 



Cliffs and rocky cafion floors. Transition Zone; San Antonio 

 and San Bernardino Mountains, southern California. Type locality: 

 Ontario Peak, California. 



Phylum SPERMATOPHYTA. 



SEED-BEARI^X. PLANTS. 



Plants producing seeds which contain the young plants in a dormant condition 

 until germination. Sporophylls arranged in groups (flowers ) of definite or indefi- 

 nite numbers, heterosporous, those bearing microsporangia ( anther-sacs ) termed 

 stamens, those producing macrosporangia ( ovules ) carpels. The gametophytes 

 very much reduced, the female being confined within the macrosporangia, where 

 its egg-cell is fertilized by the spermatozoid of the male g'ametophyte (pollen-tube). 



The seed-bearing plants form the most numerous group in existence, not less than 

 130,000 species being known. 



There are two classes in the subkingdom, which differ from each other as follows: 



.v^- 



Ovules and seeds borne on the face of a scale, not enclosed. 

 Ovules and seeds contained in a closed cavity (ovary). 



Class 1. Gymnospermac. 

 Class 2. Angiospennae. 



Class 1 GYMNOSPERMAE. 



Ovules (macrosporangia) naked, borne on the flat surface of a sporophyll, this 

 not infolding or uniting to form an ovary, sometimes apparently wanting. Pollen- 

 grains (microspores) dividing at maturity into two or more cells, one of wdiich 

 gives rise to the pollen-tube. 



The Gymnosperms are an ancient group, first known in Silurian time, and most numer- 

 ous in Triassic time. They are now represented by not more than 500 species of trees 

 and shrubs. There are six orders represented by living species: Ginkgoales (only one 

 species extant, Ginkgo biloba tnaiden-hair tree), Cycadales (fern-like tropical or sub- 

 tropical plants), Arauc'ariales, Taxales, Finales, and Gnetales. Only the three last are 

 represented in the flora of the Pacific States. The presence of ciliated spermatozoids in 

 the Ginkgoales and Cycadales, and the well developed archegonia suggest that the Gymno- 

 sperms might be more closely related to the Pteridophytes than to the Angiosperms, or, 

 what is more probable, that they represent a distinct offshoot from the former. 



Family 1. TAX ACE AE. 



Yew Family. 

 Slightly resinous and aromatic evergreen trees or shrubs, with fissured or scaly 

 bark, close-grained and durable wood. Leaves stiffs, entire, linear or lanceolate, 

 spirally arranged but usually appearing 2-ranked by a twist of the flattened and 

 decurrent petiole. Flowers dioecious, axillary, surrounded by the bud-scales, the 

 staminate composed of many anthers, each bearing several pendent pollen-sacs ; the 

 ovulate of a solitary ovule, becoming a bony seed and surrounded by a fleshy aril ; 

 cotyledons 2. 



Ten genera, the majority of which are in the southern hemisphere, where some species are important 

 forest trees. In North America only the two following genera are found: 



Fruit drupe-like, completely enclosed by the fleshy coat; endosperm ruminate; pollen-sacs in a seniicircle; 



leaves very sharp-pointed. 1- Tumion. 



Fruit surrounded by a scarlet fleshy cup; endosperm uniform; pollen-sacs in a circle around the filament; 



leaves not sharp-pointed. 2. Taxus. 



