I02 



far more favourable than the outside ones of Nature, and 

 yet despite this, it is only now and again that seedlings 

 appear of that very remarkable form. Sown on the other 

 hand in carefully sterilized pans covered with glass, it is 

 requisite to sow extremely thinly, only peppering the 

 surface so to speak, or such an abundance of prothalli, the 

 first products of spore germination, results, that it is 

 obvious every spore is capable, as we have said, of per- 

 forming its reproductive duty if not interfered with. Never- 

 theless, it is clear from the paucity of stray plants that 

 under normal conditions such interference nmst be the 

 rule rather than the exception. In this connection, indeed, 

 the record of this identical plant prove that of all the many 

 millions, all without exception must perish year after year, 

 not one surviving the infantile risks to which the tiny 

 prothalli are exposed. 



This Fern was found at the side of a country lane near 

 Drymen in Stirlingshire in 1861, and when found was 

 evidently a long-established plant with a num.ber of crowns. 

 The writer visited the spot some years ago and saw 

 the exact place in which the " find " was discovered. He, 

 like many previous visitors, made a careful search all 

 round the locality, but despite its being a particularly 

 ferny one, and the fact that one would have to multiply 

 the aforesaid millions by a good number of years, no other 

 specimen has ever been discovered, although, as we have 

 seen, it is by no means a difficult fern to raise under 

 culture, while the type is unmistakable at an early stage in 

 all its seedlings. Fertility in one direction, therefore, is 

 clearly heavily handicapped in another. In the first place, 

 the spores are absolutely microscopic, and when they ger- 

 minate the product is so tiny that any heavy shower will 

 dislodge them, while doubtless the worms, and indeed the 

 whole local insect world, are likely in their rambles to 

 destroy myriads more, to say nothing of the fact that 

 small as are the spores, they must form a source of 



