154 TAG!'; SKOOS HEHG 



Of the very numerous works on the marine Ustracods that have appeared since 

 the beginning of this period only a few of the most important can be mentioned here: W. Baird, 

 1850a. J. D. Dana, 1852, W. Liljebohg, 1853, G. O. Sahs, 1865 and 1887, G. S. Bkady, 1868b, 

 1880, F. MiJLLEK, 1870, C. Claus, 1873, 1874b, 1876 and 1891a, F. Dahl, 1888, G. S. BHAOY 

 and A. M. Norman, 1889 and 1896, G. \X. MULI.ER, 1890, 1894, 1906a and b, 1908, and 1912, 

 and N. HiRSCHMANN, 1912. 



The works from the earlier part of this period are for the most part purely classificatory. 

 Questions of oecology and comparative morphology seem as a rule to have been outside the 

 sphere of interest of the authors of this time, or were at least only cursorily discussed. These 

 works are certainly not noteworthy for any great acuteness and preciseness in establishing details 

 of morphology, on the contrary the species described during this time are treated so super- 

 ficiallv, the diagnoses often consist merely of generally formulated descriptions of the shell, 

 that in most cases it is quite impossible to identify them with certainty nowadays. Our 

 knowledge of the Ostracod system was, however, rather rapidly enlarged, the main features 

 of the natural classification of this group were already during this period brought within the 

 limits of our knowledge. 



Among the earlier works of this epoch one may without hesitation point out that of 

 W. LiLJEBORG, published in 1853: ,,D e Crustaceis ex ordinibus tribus: 

 Cladocera, Ostracoda e t Copepoda, in Scania o c c u r r e n t i b ii s" as the foremost, 

 both as regards the excellence of the drawings and the number and exactitude of the morpho- 

 logical details given. On the other hand this work is not distinguished by any systematic 

 acuteness; a striking weakness is shown, for instance, in the complete absence of any 

 classification into families; the Ostracods are in this work divided directly into 

 genera; in the morphological interpretation of some organs of the C v p r i d i n i d s 

 this author w^as also not so fortunate. In these two respects this work is far inferior to 

 J. 1). Dana's work 1852. With regard to the forms belonging to the group Cypriformes 

 W. LiLJEBORG attained much better results; these may be said to be a very great advance; 

 unfortunately, however, they could not be used to any great extent because most of the 

 work was written in Swedish. 



G. 0. Sars' two above-mentioned works, F. Muller's essay on the genus Ci/pridina, 

 1870, and C. Claus' different works all show a fairly big advance in the department of morpho- 

 logical study. G. W. MtiLLER is, however, beyond all comparison the most important author 

 for the development of this study. His monumental monograph ,,D i e O s t r a c o d e n 

 des Golfes von Neape 1", 1894, dealing with the marine s t r a c o d s in an 

 exceedingly comprehensive and exhaustive way both from the systematical, phylogenetical, 

 morphological, and oecological standpoints, immediately made this group one of the best known 

 among the marine invertebrates. 



After this work of G. W. MCli.er the study of the marine s t i' a c o d s may be said 

 to liave entered on a barren period. The succeeding works — even those of G. W. MijlJ-Eii 

 himself are practically all mere descriptions of species. There are, liowever, a few exceptions, 

 for instance N. HlHSi:il.MA\.\'s merit(ui<nis little work in 1912, especially valuable for the 



