The Entomostraca of the Scottish National Antarctic Expedition, 1902-1904. 

 By Thomas Scott, LL.D., F.L.S. Communicated by Dr J. H. ASHWORTH. 

 (With Fourteen Plates.) 



(MS. received January 24, 1912. Read February 19, 1912. Issued separately November 15, 1912.) 



CONTENTS. 



PAGE 



Introductory Statement 275 



Systematic Part 



Copepoda 281 



Cladocera 334 



Ostracoda 334 



Alphabetical Index 343 



Addenda 353 



INTRODUCTORY STATEMENT. 



The Entomostraca recorded here were collected by the S.Y. Scotia on its way to 

 and from the Antarctic, and also while carrying on investigations there during the 

 years 1902 to 1904. The Entomostraca in these collections belong chiefly to the 

 Copepoda, but the Cladocera and Ostracoda are also represented, the last by a 

 considerable number of species. These three groups are described below in the order 

 mentioned. 



THE COPEPODA. 



The Copepoda recorded in the following pages number considerably over one 

 hundred species. A fairly large proportion of them belong to the Calanoida and to 

 one or two other groups of pelagic forms ; these were, for the most part, obtained in 

 samples of plankton chiefly surface gatherings collected by tow net at various stations 

 on the outward voyage betweeen Cape Verde and the Falkland Islands. On the other 

 hand, most of the Harpacticoida, of which there are a good number, are from the 

 neighbourhood of the South Orkney Islands, but some of them were also obtained in 

 siftings from material brought up in the dredge or trawl net, and amongst organisms 

 washed from floating Gulf-weed. 



Most of the pelagic or free-swimming species from the tow-net collections are more 

 or less widely distributed, and have been described in various published works, but some 

 of them are tolerably rare. The Harpacticoida and other demersal forms are, however, 

 not so well known, and a considerable number of those recorded here appear to be 

 undescribed ; a few of them are closely related to British or other northern species, and 

 seem to lend some support to the idea of a bipolar distribution 



The occurrence at places so far distant as the Falklands and South Orkneys of 

 demersal forms identical with, or closely allied to, those of Britain and Norway has a 

 bearing on the question of distribution different from that concerning organisms living 



(REPRINTED FROM THE TRANSACTIONS OF THE ROYAL SOCIETY OF EPINBUHGH, VOL. XLVIII., PP. 521-599.) 



