476 Mr. Valentine on the Development of the Theca, 



thus differing most essentially from true seeds, while the new plant which 

 arises from them is equally perfect. This appears also to have been nearly 

 the opinion that Dillenius entertained respecting the propagation of the 

 Musci ; and it has been confirmed in later times by the celebrated Richard 

 and others." 



In the same Memoir we have the following quotation from Sprengel : 

 " 'Though,' says this naturalist, 'I have formerly been a zealous advocate for 

 Hedwig's theory of the fructification of Mosses, it has nevertheless appeared 

 to me an insurmountable objection, that the supposed anthers can again pro- 

 duce buds and strike roots, which is certainly the case with regard to the 

 disks of Polytrichum commune, Bartramia fontana, Bryum palusfre, undula- 

 tum, cuspidatum, punctatum, and with those of Tortula ruralis. In Bryum 

 ar^enteum we see the buds containing the supposed anthers constantly drop 

 off, strike root, and produce new plants : this I have observed myself times 

 but of number. Still more in point is the experiment first made by David 

 Meese, of sowing the stellulae of Polytrichum commune, containing merely 

 club-shaped bodies, when he found that plants came up, which, in their turn, 

 produced fruit. Another excellent naturalist. Dr. Roth, has made similar ob- 

 servations with regard to Hypnum squatTosum and Bryum argenteum' " " He 

 afterwards adds," say the authors of the Memoir, " ' It is more probable, there- 

 fore, that these supposed anthers are mere gemnue, produced by the superabun- 

 dance of the juices, and hence surrounded by succulent filaments.' " The latter 

 quotations contain, as far as I have been able to ascertain, the chief evi- 

 dence against the theory of Hedwig. Although such arguments establish the 

 improbability of the presence of sexes in Mosses, they by no means amount 

 to a proof of their absence. As for the observations of Sprengel and Meese, 

 they are very defective. Mr. Brown, in a conversation which took place 

 about three years ago on this subject, very justly objected to the conclusions 

 drawn from these experiments. From the statement of Sprengel, it does not 

 appear that the supposed anthers were actually seen to grow: and it seems 

 most probable that the growth took place in the axillae of the scales, which 

 formed the bud containing the anthers. Every one acquainted with vegetable 

 physiology is aware of the great tendency to development existing in the 

 axillae of leaves, especially in those which form the scales of a bud. To have 



