THE HIGHER CRYPTO GAMI A. 305 



account of the external phenomena of the germination. 

 Vaucher found* that spores of Eq. Telmaieia and palustre, 

 when sown in flower-pots, became swollen, and divided at 

 the apex first into two, and then into several lobes. These 

 lobes sent forth rootlets which affixed themselves to the 

 ground, and ultimately formed bright green patches some- 

 times as much as a line in diameter, and resembling a 

 small Aneura. They remained in this condition for about 

 two months without growing perceptibly. At last a 

 green point grew out from the middle of the patch, which 

 point, as it became larger, exhibited a frill at its base, then 

 a second, and then a third frill, from the apex of which the 

 young stem arose. Vaucher distinguished the two kinds 

 of roots of the prothallium and of the embryo ; he stated 

 that the first formed roots were numerous, although thin 

 and stunted ; but that a vigorous root was produced from 

 the stem of the young Equisetum, and penetrated perpen- 

 dicularly into the ground. 



Vaucher's observations remained for some time quite 

 unsupported. In 1826 Bischoff's experiments only re- 

 sulted in the production of prothallia, all of which after- 

 wards decayed. He showed, however, clearly, f that the 

 processes described by Agarclh and Vaucher as cotyledons, 

 were only an imperfect, or intermediate germ-growth (a 

 proembryo or prothallium), which, as in most other cryp- 

 togamic plants, afterwards became transformed into a 

 true embryo. In the autumn of the same year Bischoff 

 supplemented his observations by publishing the result of 

 his examination of some germ-plants of JEq. palustre, found 

 in the autumn of 1827, in their native habitats .% He 

 observed that the young germ-plants burst forth from the 

 interior of the prothallium, and he disproved Vaucher's 

 statement, — viz., that the root which penetrates into the 

 earth is afterwards transformed into the rhizome — by show- 

 ing that at a very early period the germ-plant produces 

 lateral shoots, whose growth from the commencement fol- 

 lows a horizontal or dowmward direction. He noticed also 



* 'Mem. d. Musee.,' vol. x, 1823, p. 429. 



f ' Kryptog. Gewachse,' i. Nurnbeny, 1828, p. 43. 



% See 'N. A. A. C. L., 5 vol. xiv, p. 785. 



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