180 VHILOSOPHICAL TRANSACTIONS. | ANNO 1751. 



The male plant, which is continually covered with water, has a short stalk, on 

 the top of which its flowers are produced. As this top never reaches the sur- 

 face of the water, the flowers are thrown off" from it, and come unopened to the 

 surface of the water ; where, as soon as they arrive, by the action of the air, 

 they expand themselves, and swim round the female flowers, which are blown at 

 the same time. These last have a long spiral foot-stalk, by which they attain 

 the surface of the water, and remaining there in flower a few days, are impreg- 

 nated by the male flowers detached from the stalk at the bottom. This opera- 

 tion seems to be thus directed, as the farina foecundans could not exert its effects 

 in so dense a medium as water; and we find that even the hermaphrodite flowers 

 of water-plants, such as those of potamogiton, renunculus aquaticus, hottonia, 

 and nymphasa, never expand themselves till they reach the surface of the water. 



But to return : it was not possible for Mr. W. without premising these things, 

 to make evident what he just now mentioned, in regard to the falsely denomi- 

 nating the sexes of plants ; as it is to this last class that the wrong application 

 has been made by botanical writers. This error seems to have been first in- 

 troduced as early as Dioscorides, and has been continued through a great va- 

 riety of writers, even to our own time. It is most certain, that those plants, 

 which produce the seed, ought to be considered as females ; but it happens that 

 in the French and dog's mercury, the seeds are produced in the female plants by 

 pairs ; and these are contained in a capsule, which was thought to resemble the 

 scrotum of animals; and from this testiculated appearance they called these 

 plants males, and the others females. Thus, for example, Dioscorides, when 

 treating of mercurialis, or what we here call French mercury, says, " the seed 

 of the female is produced in bunches, and is copious ; that of the male grows 

 near the leaves ; it is small and round, and disposed in pairs like testicles." Do 

 donaeus, Lobel, Delechamp, John and Caspar Bauhin, Morrison, Tournefort, 

 and Boerhaave, in their several works, have followed Dioscorides, and have de- 

 nominated the seed-bearing plant of this kind, the male ; and the other, the fe- 

 male. Fuchsius and John Bauhin likewise call the cynocrambe or dog's mer 

 cury, which bears fruit, the male ; and the spiked one with male flowers only, 

 the female. This mistake is observable in hemp, hops, and spinach. 



We observe that the operations of nature are carried on most usually by cer- 

 tain general laws, from which however she sometimes deviates. Thus almost 

 all plants have either hermaphrodite flowers, or male and female flowers, grow- 

 ing from the same root, or male and female flowers from different roots : but 

 there are a few of another class, which fi-om the same root furnish either male 

 and hermaphrodite flowers, or female and hermaphrodite flowers. Of this kind 

 are the mulberry-tree, the musa or plantain-tree, white hellebore, pellitory, ar- 

 rachj the ash-tree, and a few others. But of this class the empetrum or berry- 



