914 VI. LTCOPODIACEJE. 



SPOKAISTGIA {oophoridia, spherotheca), less numerous, solitary and very large, or 4-5-6 

 at the base of the spike, or indeterminate in number, and mixed with the micro- 

 sporangia, sometimes placed on distinct spikes, and as it were monoecious, 2-3-lobed 

 and valved, and containing 3-4-8 sub-globose bodies [macrospores). The macko- 

 SPORES are the true spores, which are much larger than the microspores, and alone 

 have the power of germinating ; they are rounded on the outer side, and present 

 where they are in contact within the sporangium 3-4 triangular faces, somewhat 

 flattened, and separated by more or less projecting lines; the prothallus springs 

 from the point where these lines meet. Prothalltis orbicular, composed of 3—4 

 layers of cells ; the archegonia are developed on its surface, and are somewhat similar 

 to those of Ferns. No one has yet seen the germination of the microspoveSj which 

 are only sexual organs of all Lycopods but Selaginella. 



GENEEA. 

 Psilotum. Tmesipteris. Lycopodium. Selaginella. Phylloglossum. 



The fertilization of Lycopocls is stilt very obscure. In true Lycoipods, in which the sporocarps are 

 all alike {Lycopodium, PsUotwm, &c.), we only find microspores, apparently homogeneous, but perhaps 

 of two different natures, mixed in the same sporangium. It is different in Selaginella, where we can 

 trace the development of the embryonic vesicle and of the embryo, precisely as in Ferns. One arche- 

 gonium alone is fertile, and it is not rare to find at the base of the young plant the remains of the pro- 

 thallus laden with sterile archegonia. One peculiarity of the formation of the embryo in Selaginella 

 is, that at the moment when fertilization takes place, the cavity of the spore partially fills with a very 

 delicate cellular tissue. The embryonic vesicle grows, becomes divided, and lengthens into a filament 

 which buries itself in the mid(^le of this fresh tissue. Then the lower cells of the filament multiply and 

 form a small cellular mass, frosr^ which spring the first bud and the radicle. Thus formed, the embryo 

 quickly rends the prothallus, ar^d gives birth to a young plant. 



Lycopodiaeeis, as at present defined, are closely allied to Isoetete only ; they diff^er in the regular 

 and valvate dehiscence of the sporangia and the number of the macrospores, which are four and rarely 

 eight, while they are numerous in Isoeteee. 



The creeping species grow at one end, while the other end decays, so that they travel, like the rhi- 

 zomes of many Phsenogams (Carex, Iris, Polyffonaticm, &c.). Some Lycopods (i. venusttdmn, ctirvatwn, 

 &e.) recall by their dichotomous and leafy stems certain fossils of the eoal formation (Calamites) ; 

 their cone-shaped fructification resembles the structure of another fossil, the Triplosporites, described 

 by R. Brown, and placed by him between Zycopodiaeeee and Ophioglossea. There is also a reseni- 

 blance between Lycopodiacem and Gymnosperins. 



About 350 Lycopodiacea are now known, of which 100 are Lycopods and 200 Selaginella''. This 

 group is represented up to the polar regions by Lycopodium Selago, alpinwin, eomplanatum, inaf/dlnnicum, 

 as well as by Selaginella sjnnul-osa, helvetica and denticulata, which advance to the snow limit, where 

 S. sangitinolenta is met with on the Altai aiid towards the mouth of the Amoor. PhyUoglosmm (P. 

 Sanyuisorha, Spg.),, the smallest known species, resembling in habit a very small Plantago pusilla 

 (an inch or two in height), is found on the west coast of Australia, and in New Zealand. Tmesipteris 

 belongs to Australia, Psilotmn to Madagascar, the Mascarene, ^he Moluccas and the Sandwich Islands. 



We have no very precise knowledge of the properties oi Lycopodiaceee. The Club Moss (£. olavatum), 

 wbich grows in the mountainous woods of Europe, is an insipid herb, still administered in Russia for 

 hydrophobia. The granules which fill the sporangia are extremely infliunmable, and foriiSj ' vegetable 

 sulphur,' whicli is valuable for theatrical purposes [to produce lightning]. This dust is also used for 

 rolling pills in, and medicinally as a desiccator, to cure excoriations in the skin of young infants. A 

 decoction of L. Sdugo is emetic, drastic, vermifuge and emmenagogue ; L. myrsimitis and eatharticum are 

 also considered purgative. The root of X, FMegmaria is slightly salt; the Indiana attribute, to it mar- 



