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SCIENCE 



[N. S. Vol. XLV. No. 1157 



research are often found in combination. 

 Nevertheless, both writers and works, as a 

 rule, follow a main trend and may be ar- 

 ranged under one or another of the prin- 

 cipal subjects, although important contri- 

 butions under a difiPerent subject may also 

 be included. Bach of the subjects, in turn, 

 may be divided into periods according to 

 the principal influence at work and the 

 progress along a special line of develop- 

 ment. One period naturally passes over 

 into another, the way being prepared by 

 those writers whose work may be termed 

 anticipatory and the inception of a new 

 period being marked by some writer, or 

 group of writers, whose advance is more 

 pronounced and whose innovations have 

 had the greatest influence. In taxonomic 

 lines, the beginnings are to be found in the 

 earliest writers, both botanical and non-bo- 

 tanical, and the progress in the study of the 

 marine alg^ was necessarily slow until the 

 study of more and more of the more com- 

 plex plants had pointed the way and, to 

 some extent at least, the methods. 



Naturally the earlier work on the marine 

 algse, as on higher plants, was taxonomic, 

 particularly descriptive. In the earlier 

 period mere mention was made in general, 

 but Morison, Eay, Hudson, Dillenius and 

 Linnaeus, for example, laid the foundations 

 upon which Goodenough and "Woodward, 

 Gmelin, Turner, Esper, Poiret, De Can- 

 doUe and others built more solidly. Gmelin 

 (in 1768) published the first book on marine 

 algffi, entitling it ' ' Historia Fucorum. ' ' In 

 the latter portion of this first period Roth 

 and Stackhouse prepared for the coming of 

 a more logical treatment, especially as to 

 genera. The older method divided the spe- 

 cies of algas between such polymorphic and 

 indefinite genera as Fucus, Viva, Conferva, 

 Byssus and Tremella. Roth and Stack- 

 house added a few new ones, but these are 

 also mostly of extensive application and of 

 indefinite character. 



The second period of taxonomic progress 

 dates from 1813, when J. V. Lamouroux 

 published his "Essai sur les genres de la 

 famille de Thassiophytes non articulees." 

 Lamouroux practically instituted genera 

 in very much the modern sense and laid 

 the foundation for future work. Hence- 

 forth both the general morphology and the 

 character of the fructification were taken 

 into account in taxonomic work. Besides 

 Lamouroux Bory de Saint Vincent, C. A. 

 Agardh and Lyngbye were responsible for 

 advance in the earlier part of this second 

 taxonomic period. They were succeeded by 

 Greville, Montague, Decaisne, J. G. Agardh, 

 J. D. Hooker, "W. H. Harvey, Kiitzing, J. 

 E. Areschoug, Ardissone, Zanardini, Ru- 

 preeht and others. 



The latter part of the second taxonomic 

 period is merged with and came under the 

 influence of a more careful morphologic 

 and histologic study and a closer atten- 

 tion to the structure and development of 

 the organs of fructification. Kiitzing 

 did much to promote this in his "Phy- 

 cologia Generalis" (1843) and his "Tab- 

 ular Phycologicffi" (1845-1869). Naegeli, 

 Cramer, Zanardini and others assisted 

 in the same dii'ection. These works mark 

 the passing over into the third distinct 

 taxonomic period which may be said to 

 have begun with Thuret and Bornet and 

 which has continued down to our own 

 times. Its earlier inquiry into the nature 

 of the reproductive bodies dates from 

 Thuret 's classic researches on the zoospores 

 and antheridia of the algse (1845-1855). 

 This was continued into the discoveries as 

 to the modes of development of the cysto- 

 earp in the red algse and all came as a cul- 

 mination of the similar work by Prings- 

 heim, Naegeli and others. The magnificent 

 "Notes Algologiques" (1876, 1880) and 

 "Etudes Phycologiques" (1878) will long 

 remain as examples of the finest contribu- 

 tions along these various lines of histolog- 



