353 



IX. A M onograph of the Becent British Ostracoda. 



By George Stewardson Brady, Esq. Communicated by Dr. Sclater, F.L.S. fyc. 



(Plates XXIII.-XLI.) 



Read May 3rd, 1866. 



o 



* 



SlNCE the publication, in 1850, of Dr. Band's work on the British Entomostraca, 

 much has been done towards the elucidation of the anatomy and physiology, as well as 

 the distribution and zoological classification, of these animals, and probably no group 

 has received a larger share of attention than the Ostracoda. The interest attaching to 

 this group is much enhanced by the fact that they alone, of all the higher llicrozoa, are 

 found in the fossil state in sufficient numbers to afford grounds for any exact comparison 

 between the fauna of the present and those of bygone ages; and it is, of course, only 

 by the diligent collecting and accurate description, both by pen and pencil, of the form - 



in our lakes and seas, as well as of fossil species, that much progress in this 



direction can be made. 



The classification hitherto in vogue has rested almost entirely upon external shell - 

 characters and mode of hingement ; and, seeing that by far the greater number of 

 species have been described from fossil specimens, no other method was, of course, prac- 

 ticable. But though the careful study of the shells, which has necessarily accompanied 

 such a plan of classification has been very advantageous, and has, indeed, resulted to a 

 considerable extent in a really natural grouping and arrangement of genera ami species, 

 it is obviously an unsatisfactorv and unsound basis of classification ; and much has been 

 ntly done by various continental authors to increase our knowledge of the mmute 

 structure of the animals themselves. Among the naturalists who have been foremost 

 in this WO rk may be mentioned Professor Lilljeborg, Fischer, Zenker, and G. fears. 

 The admirable memoir of the last-named author, 'Oversigt af Xorges marine Ostra 

 coder/ published in 1865, contains descriptions of all known Norwegian marine species 

 — according to the anatomical characters of the annuals, the structure oi 

 most of which is there for the first time minutely described. Tins work forms, mdeed, 



r 



ified 



- .poch in the study of the Ostracoda ; and its anthor deserves the warmest acknow 

 ledints of all car iuologists for the light which he has thrown, at the expense oi 



«u4 time and labour, on °the minute structure and affinities of the «*""£2£ 



To British naturalists the work is, indeed, espeetally valuable, on ac com t o 



treats 

 ! close 



. . -i , +i,« fminis of the two countries ; and I have, 



relationship existing between the faunas oi me M»*riW 



this monograph, adopted, with hut litUc ^^^SS^STt 



propounded by the author of the < Oversigt. The greatest 



« experienced arises from the fact that |j fe £ JJjJ ^ ^J** 



specimens have been dried in the first instance with the mud or sana ; 



VOL. XXVI. 



/■v 



