67 



of flashes of light; the lower ones contain larger grains, equal in size 

 to the seed of many phaenogamous plants. This double mode of fruc- 

 tification has excited the admiration of botanists from the earliest pe- 

 riod, and given rise to a variety of conjectures ; some have contended 

 that both the large and small grains are productive seeds, others that 

 the smaller bodies are true seeds, the large ones gemmae or buds ; 

 others that the smaller are abortive and the larger productive seeds ; 

 and others again that the larger ones only are seed, the smaller ones 

 being grains of pollen. 



Wahlenberg* has given a very clear and accurate description of this 

 twofold fructification. He observes that the capsules containing the 

 granifonn seeds are subquadrilocular, in reality bivalve, but sometimes 

 dehiscing in four directions ; they occupy the lower portion of the 

 spike, and are larger and more protuberant than those above. The 

 seeds are always four in number, and are so squeezed and pressed to- 

 gether that three triangular areas are produced at the base of each ; in 

 this particular they so much resemble the seeds of Isoetes lacustris, 

 that, agreeing as the plants do in so many other respects, it is hardly 

 possible to doubt their being closely related. The seeds are nearly 

 as large as those of the poppy, and invariably fall from the capsule en- 

 tire and are scattered upon the earth, a circumstance quite conclusive 

 against their being anthers, as suggested by Hedwig. Capsules filled 

 with the powdery seed common to the other Lycopodia and the bi- 

 valved ferns, occur in the axils of the upper bracts ; this powder con- 

 sists of somewhat hirsute granules, four of which are combined in a 

 tetrahedron, exactly like the seeds in the lower capsules, exhibiting a 

 very obvious analogy between the two kinds of seed, and leaving no 

 doubt of their having the same origin. If therefore the powder emit- 

 ted from the capsules of Botrychium Lunaria be true seed, it follows 

 that the powder produced by the capsules of Lycopodium Selaginoi- 

 des is seed also. It cannot be male pollen, its appearance being pre- 

 cisely synchronous with that of the mature seeds. The spike itself is 

 annual, decaying immediately after it has fruited in July or the begin- 

 ning of August, and the next year a new spike springs from some other 

 part of the prostrate stem, on no part of which can a trace of future 

 capsules be found. From these circumstances it seems probable that 

 the only difference between the granules is that of size, each being to 

 be regarded as true seed ; a somewhat analogous discrepancy occurs 

 in the varied form of the seeds of spinach. Edward Newman. 



(To be continued). 

 * Flora Lapponica, 292. 



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