258 ON THE PRESENT STATE OF OUR 



growth of tlie vegetative organs with the same mastery as iu liis treatise 

 0!i the algiP. Hugo vou Mohl explains in a very simple manner the 

 interesting phenomena attending the vegetation of peat-mosses in a 

 short but thorough essay on their perforated cells. Carl Miiller explains 

 the remarkable existence of lamels on the leaves of the polytrichaceoe, 

 and Lantzius Beuinga shows how the ripe capsule, the spores and the 

 peristome are developed. Schimper's " it\'c/<erc/ics sur Vorganogmphie 

 (les mousses^^ and the introduction of his " Synopsis Muscorum europaeo- 

 rum^'' are of great value ; for, in both works, we not only find the results 

 of organographic researches gathered, but we also find them enriched 

 by numerous observations of his own. 



Passing to the most important works on classification, we must grant 

 the first place to Xees von Esenbeck for his excellent natural history of 

 European liverworts, since it is the foundation of our present views of 

 this branch of botany. He divides up the genera of his predecessors 

 in a very natural manner, and his descriptions of species are masterly. 

 His distinguishing characteristics are always sharply defined. The 

 principles applied with such excellent success on European species 

 were also brought to bear on exotics by Kees von Esenbeck, Gottschee, 

 and Lindenberg, who published together the Syno2)sis Hcpaticarnm, 

 which is considered the standard work. Unfortunately, there are no 

 illustrations of all species of this class ; for the best are still to be found 

 in " British Jiingennannicc,''^ published 1820, or thereabouts, by Hooker. 

 Lindenberg endeavored to supply the deficiency by his iSpecics Ilepati- 

 canon, but after several excellent monographs of single genera had ap- 

 peared the i)ublication ceased. Later ones were limited to the description 

 of new material or the better description of single genera. Among 

 them must be mentioned the excellent treatises of Gottschee, the Hcpa- 

 ticw Javaniccc of Van der Sande Lacosta, and the works of Montaigne, 

 Taylor, Mitten, and De Notaris. 



The appearance of the Bri/ohgia Europca Qxerched a reforming inllu- 

 ence on the study of the mosses. Several excellent scholars, Avith W. 

 Ph. Schimper at tlie head, determined to describe and depict all species 

 of mosses known in Europe in a manner adequate to the demands of the 

 time. They mutually controlled their results for fifteen years, when the 

 work was completed in six stately volumes of more than six hundred 

 tables, and it now forms our basis for the study of these plants. In it 

 the genera were more naturally (although sometimes weakly) divided 

 .and better arranged. In the description of the species, the organograph- 

 ,ical and anatomical points, especially the reticulation of the leaves, were 

 for the first time considered. Excellent illustrations facilitate the recog- 

 nition of the species, and make it possible in some cases whifth had 

 before presented dilliculties. After the appearance of the Bryology, 

 Schiuiper published a fine monograph on the European peatmoss, and 

 a more general Si/nopsis ]\Iusc()nim Enropeorum. It is hoped that this 

 excellent. scholar will soon be able to realize his long-cherished plan, the 



