278 CONCLUDING KEMAEKS. Chaf. IX. 



children of a single plant would nearly (in the ratio of 

 47 to 50) clothe with one uniform green carpet tho 

 entire surface of the land throughout the globe. Bu*. 

 the number of seeds produced by one of our common 

 British orchids is as nothing compared to that of some 

 of the exotic kinds. Mr. Scott found that the capsule 

 of an Acropera contained 371,250 seeds ; and judging 

 from the number of flowers, a single plant would some- 

 times yield about seventy-four millions of seeds. 

 Fritz Miiller found 1,756,-140 seeds in a single capsule 

 of a Maxillaria ; and the same plant sometimes bore 

 half-a-dozen such capsules. I may add that by 

 counting the packets of pollen (one of which was broken 

 up under the microscope) I estimated that the number 

 of pollen-grains, each of which emits its tube, in it 

 single anther of Orchis mascula was 122,400. Amici* 

 estimated the number in 0. morio at 120,300. As 

 these two species apparently do not produce more 

 seed than the allied 0. maeulata, a capsule of which 

 contained 6200 seeds, we see that there are about 

 twenty pollen-grains for each ovule. According to 

 this standard, the number of jjollen-grains in the 

 anther of a single flower of the Maxillaria which 

 yielded 1,756,440 seeds must be prodigious. 



What checks the unlimited multiplication of the 

 Orchidese throughout the world is not known. The 

 minute seeds within their light coats are well fitted 

 for wide dissemination ; and I have several times 

 observed seedlings springing up in my orchard and in 

 a newly-planted wood, which must have come from a 

 considerable distance. This was especially the case 

 with Epij)actis latifoUa ; and an instance has been re- 

 corded by a good observer j of seedlings of this plant 



* Mohl, ' The Vegetable Cell,' t Mr. Bree, in « r.ondnn's :\rag 



tn»U8lat«i by Heufrey, p. 133. of Nat Hist,' vol. ii. 1S29, p. 70. 



