86 PERIOD III. 



a way so far not understood. Gaertner, a contem- 

 porary of Linnaeus, pointed out one important respect 

 in which the spores of cryptogams differ from the seeds 

 of flowering plants, viz. that they contain no embryo. 



Ferns. Even before the age of Linnaeus it was known 

 that little ferns spring up around the old ones, and that 

 a fine dust can be shaken from the brown patches on 

 the back of ripe fern-leaves. The dust was reputed to 

 be the seed of the fern, and in an age which believed in 

 magic the invisibility of fern-seed made it easy to suppose 

 that the possessor of fern-seed would become invisible 

 also. When the microscope began to be applied to 

 minute natural objects, the brown patches of the fern- 

 leaf were closely examined. William Cole of Bristol 

 (1669), Malpighi, Grew, Swammerdam, Leeuwenhoek, 

 and others, found the stalked capsules (sporangia), their 

 elastic ring and the minute bodies (spores) lodged within 

 them ; it seemed obvious to call the capsules ovaries and 

 the spores seeds. Some time in the latter part of the 

 seventeenth century Robert Morison, professor of botany 

 at Oxford, who died in 1683, sowed spores of the 

 harts-tongue fern, and next year got an abundant crop 

 of prothalli, which he took to be the cotyledons. A little 

 later, when it had been proved that flowering plants 

 possess male and female organs, diligent search was 

 made for the stamens and pistils of ferns and mosses, 

 which of course could not be found, though identifica- 

 tions, sometimes based upon a real analogy, were con- 

 tinually announced. Late in the eighteenth century one 

 John Lindsay, a surgeon in Jamaica, who was blest with 

 leisure and a good microscope, repeated the experiment 

 of Morison, which seems to have been almost forgotten. 

 Having remarked that after the rains young ferns sprang 

 up in shady places where the earth had been disturbed* 



