THE GENESIS OF PLANT-OFFSPEING. 



1. ASEXUAL REPRODUCTION. 



Spores and Thallidia. — Buds on Eoots>. — Buds on Stems. — Buds on Leaves. 



SPORES AND THALLIDIA. 



In the chapters on ferns in the old herbals, attention is invariably directed to 

 the extraordinary phenomenon that the plants in question do not produce flowers 

 or fruit, and yet propagate their kind and multiply abundantly, and the remark is 

 made that these plants will often spring up quite unexpectedly in caves, or in the 

 cracks of old walls, without any seeds having been previously perceptible there. 

 Hence in Germany a fabulous story was invented that the seeds of ferns were 

 formed in a mysterious manner at the time of the summer solstice only, and that 

 these seeds could only be collected on Midsummer Eve by persons initiated in the 

 mystery who made use of certain magic words on the occasion. Hieronymus Bock 

 or Tragus, as he called himself in accordance with the then prevailing fashion of 

 translating names into Greek, preacher and physician at Hornbach in 1532, was 

 the iirst to contradict this childish superstition, and to convince himself of the 

 possibility of obtaining "fern-seeds" without the use of incantations. In his 

 Herbal, published in 1539, he gives the following account, which is in many respects 

 interesting, of his endeavours to collect the seeds of ferns : " All our teachers write 

 that the fern bears neither flower nor seed; nevertheless, I have four times looked 

 for the seed in the night of Midsummer Eve, and have found early in the morning 

 before daybreak small black seeds like poppy-seeds on cloths and on the broad 

 leaves of mullein beneath the stems in varying quantities. ... I have used 

 no charm or spell in this matter, but have looked for the seeds without any super- 

 stition and have found them. One year, however, I found more than another, and 

 I have sometimes been out without success. I have not gone alone to fetch the 

 seeds, but have taken two others with me, and have made a great fire in an unfre- 

 quented spot and let it burn all through the night. How the thing came to pass, 

 and what secret nature intends to reveal by it, I cannot tell. I have stated all 

 this because all our teachers describe the fern as being without seeds." 



There can be no doubt that by the brown seeds Hieronymus Bock meant those 

 structures which, about two centuries later, were named " spores" by Linnaeus. But 

 even in the time of Linnaeus the whole subject of spores, especially in their relation 

 to fruit, was shrouded in complete obscurity. The word "spore" is derived from 



