236 The Anatomy of Plants book 11 



The same was the case with that of Ophioglossum peduncu- 

 latum, which was described by Mettenius in 1856. In 

 1893 the former of the two was investigated again by 

 Campbell, and in 1897 very completely by Jeffrey ; the 

 latter described it from its very young condition. Campbell 

 described in 1895 the prothallium of Ophioderma pendulum 

 also. He showed too that a mycorrhiza is present in the 

 prothallium of Botrychium. 



The Marattiaceae formed the subject of one of Bower's 

 ' Studies '. Other workers on this family included Met- 

 tenius (1864), Tschistiakoff (1874), and Farmer (1892), all 

 of whom carried out researches on Angiopteris. Campbell 

 gave an account of the development of Marattia in 1894, 

 but though this was the first detailed account of the whole 

 fern, its sori had been investigated and described by Russow 

 in 1871, and by Luerssen in 1872. The germination of 

 the spores and the development of the prothallia of Angio- 

 pteris and Marattia were described by Luerssen in 1875, and 

 Jonkmann in 1878 ; those of Kaulfussia by Jonkmann in 

 1879, and those of Danaea by Brebner in 1896. The latter 

 also investigated the embryogeny of Danaea. 



Work on the higher Ferns was extensive and varied. 

 Sadebeck investigated the anatomy and development of 

 their leaves in 1874, Van Tieghem made an exhaustive 

 study of their roots in 1883, which was supplemented by 

 a paper on the lateral roots by Lachmann in 1889. A more 

 accurate description of the development of the sporangia 

 than had been given before was published in 1888 by 

 Kundig, who was confirmed by Muller in 1893. The 

 structure of the apical meristems was studied exhaustively 

 by Bower in 1889. 



In 1877 Prantl carried out an investigation of the 

 sporangia of the Osmundaceae. Their embryogeny was 

 studied by Kny in 1872, and by Campbell in 1892. 



Rauwenhoff described the germination of the spores and 



