Chap. IX. CONCLUDING EEMAEKS. 277 



Orchids in vast profusion. Not that such profusion 

 is anything to boast of; for the production of an almost 

 infinite number of seeds or eggs, is undoubtedly a sign 

 of lowness of organisation. That a plant, not being 

 an annual, should escape extinction, chiefly by the 

 production of a vast number of seeds or seedlings, 

 shows a poverty of contrivance, or a want of some 

 fitting protection against other dangers. I was curious 

 to estimate the number of seeds produced by some 

 few Orchids ; so I took a ripe capsule of Cephalanfhera 

 grandiflora, and arranged the seeds on a long ruled 

 line as equably as I could in a narrow hillock ; and 

 then counted the seeds in an accurately measured 

 length of one-tenth of an inch. In this way the con- 

 tents of the' capsule were estimated at 6020 seeds, and 

 very few of these were bad; the four capsules borne 

 by the same plant would have therefore contained 

 24,080 seeds. Estimating in the same manner the 

 smaller seeds of Orchis maculata, I found the number 

 nearly the same, viz., 6200 ; and, as I have often seen 

 above thirty capsules on the same plant, the total 

 amount would be 186,300. As this Orchid is perennial, 

 and cannot in most places be increasing in number, 

 one seed alone of this large number yields a mature 

 plant once in every few years. 



To give an idea what the above figures really mean, 

 I will briefly show the possible rate of increase of 0. 

 maculata : an acre of land would hold 174,240 plants, 

 each having a space of six inches square, and this 

 would be just sufficient for their growth ; so that, 

 making the fair allowance of 400 bad seeds in each 

 capsule, an acre would be thickly clothed by the pro- 

 geny of a single plant. At the same rate of increase, 

 the grandchildren would cover a space slightly exceed- 

 ing the island of Anglesea ; and the great grand- 



