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remarkable figures. In speaking of Orchis maculata, our common 

 spotted orchid, he estimated the number of seeds in a capsule at 

 6,200, and as a plant frequently has thirty capsules, the total number of 

 seeds amounts to 186,300. He gives a graphic picture showing how 

 an acre would hold 174,240 plants, each having a space of six inches 

 square, or in other words one plant could, at the end of one year, 

 completely cover an acre and to spare, if every seed germinated. In 

 tropical orchids the number of seeds is very much greater, even for 

 a single pod, apart from the usually much larger number of flowers 

 borne on a single spike. The notorious case of Maxillaria may be 

 cited, in which Fritz Miiller found 1,756,440 seeds in a single 

 capsule. Maxillaria bears only a single flower however, and it is 

 quite possible that some species of Cat/leva and Lcelia, which bear 

 from three to seven flowers, may in the aggregate occasionally bear 

 even more seeds than the astonishing total of Maxillaria. The, I 

 believe, invariable minuteness of the seeds is very remarkable. I 

 well remember the first time I saw a large pod of the common 

 Odontoglossum crispum, measuring about three inches by one inch, 

 split with -a little heap of what looked like sawdust beneath it. The 

 sawdust I was told was the seeds. It is the same with vast numbers 

 of orchids, if not actually with all. Yet, with all the abundance of 

 seeds, orchids are rarely conspicuously abundant. In the case of 

 those species that cannot grow under any but very specialised 

 conditions, it is quite understandable that a large number perish for 

 want of the proper conditions. But in the case of the common 

 British Orchis maculata, one frequently finds, perhaps, twenty or 

 thirty plants only in a large meadow, where from the fecundity of 

 the plant one would expect as many thousands. The seeds being 

 so very small and light, probably large numbers are disseminated 

 and carried away from what would have been a suitable nursery for 

 their upbringing. Yet orchids, or many of them, are very local 

 plants, so it is evident there must be an enormous amount of waste 

 continually going on. 



Fertilisation of by far the greater number of orchids is by insects ; 

 but in some cases, such as with our Ophrys apifera or bee orchid, 

 there is self-fertilisation accomplished by the wind. Self-fertilisation 

 is much less common in orchids generally than cross-fertilisation by 

 some agent, such as bees, flies, moths, etc. It is usually also con- 

 fined to terrestrial orchids, yet many terrestrial orchids are just as 

 beautifully adapted for cross-fertilisation as are tropical epiphytal 

 orchids. It is well known, however, among orchid collectors that 

 notwithstanding the numbers of flowers seed-pods are in comparison 

 quite scarce. Parasitic enemies on the agents of fertilisation — the 

 bees, etc. — keep down any great increase in their numbers, and 

 occasionally, as one knows, especially in the case of moths, a species 

 can all but die out for years at atime. It is easy to imagine what would 

 become of the plant that was perhaps dependent on that moth for its 

 fertilisation. Or again, if one considers the case of a common orchid, 



