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flowerless plants, are very much more numerous than flowering plants. 

 Great numbers of them are very small, so small indeed, that, but 

 for the microscope, their very existence would never have been 

 known. Others, such as tree ferns, really reach the dimensions of 

 small trees, and are highly ornamental, but our own country pro- 

 duces nothing in the way of cryptogamic vegetation taller than 

 common brake or bracken. That which, in a way, represents the 

 seed of flowering plants in the spore, and this tiny thing often gives 

 rise to the new plant by a very round-about process. It will bring 

 us, by a few interesting steps, to the subject of this evening, if we 

 look at the list of cryptogamic families and arrange them " in order 

 of merit," or, in other words, give them rank according to their 

 structure. The presence of wood (fibro-vascular bundles), places 

 the Filices, Equisetaceae, and Lycopodiaceae, above those orders 

 which are made up of cellular tissue only. Again, those orders 

 which, although made up wholly of cellular tissue, present a 

 distinction of parts are higher in the scale than those which do not. 

 Last, then, come plants made up of cellular tissue, but consisting 

 of a network of threads, or a more or less leaf -like expansion, called 

 a thallus, and not having root, stem, or leaves distinguishable from 

 each other. The thallus-producing plants are called Thallogens or 

 Ihallophytes, and constitute what used to be called the orders Algse, 

 Lichenes, and Fungi. [You will bear in mind that a mushroom is 

 not the plant proper, but only the fructifying apparatus, the 

 vegetative portion (mycelium) called mushroom spawn and com- 

 posed of a network of threads, being underground] . Agreeing in 

 certain points, as in the absence of stomata and in not developing a 

 prothallus in germination, these orders differ from each other a good 

 deal — at least in their higher forms. Fungi are much lower in the 

 scale than Algae, because they contain no chlorophyll and are there- 

 fore unable to take up and assimilate gaseous food. Chlorophyll 

 does occur in Lichens, but only in certain small cells, known as 

 gonidia, and usually abundant in what is called the gonidial layer. 

 In the eyes of the student these chlorophyll-containing cells are 

 of great importance, because over them rages chronic war. They 

 are indeed a battle ground on which is now being fought out the 

 question as to what Lichens really are and what they are not. 

 The ablest men are to the front in this scientific campaign, the 

 real nature of the gonidia being " the question in dispute." 

 Schwendener, following up the researches of DeBary, about 20 

 years back, took out his position thus — Lichens, said he, are not 

 simple but composite organisms — they are not an autonomous 

 group at all, but dual growths, neither one thing nor the other 

 but a mixture. Their gonidia are neither more nor less than so 

 jnany simple green or greenish-blue Jlgce, whilst the other portions 



