JOUENAL 



OF THE 



ROYAL MICROSCOPICAL SOCIETY 



JUNE, 1909 



TRANSACTIONS OF THE SOCIETY. 



X. — On the Fresh-water Crustacea of Algeria and Tunisia. 

 By Robert Gurxey. 



(Read February 17, 1909.) 

 Plates VII. to XIV. 



In the following paper I propose to give the results of the ex- 

 amination of collections made during a visit to Algeria and Tunisia 

 in February and March 1906. Thirty-one days in all were spent in 

 the country, and collections were made in Algiers, Constantine, 

 Biskra, and Hammam Meskhoutine in Algeria, and in the neigh- 

 bourhood of Tunis, as opportunity offered. 



The weather of early February was bitterly cold and wet, snow 

 falling heavily on our arrival in Algiers, and so heavily on the 

 high plateaux as to block the line to Constantine for some days. 

 It is probable that the coldness of the spring retarded the appear- 

 ance of the Entomostraca to some extent, so that my earlier 

 collections were poorer in species than they should have been. It 

 was probably for this reason that I found no specimens of Apus 

 or Estheria at Biskra, though nauplii of the latter were met with. 

 On the other hand the abundance of rain provided pools of water 

 which, in a drier season, would not have existed. The conditions 

 are so different in the dry and wet seasons of the year that it is 

 difficult for a stranger visiting the country to form a true idea of 

 the usual state of affairs. 



The fresh-water Crustacea of Algeria are better known than 

 those of any other part of Africa, but, even here, a great deal of 

 work remains to be done. The Ostracoda contained in my collec- 

 tions have not yet been worked out, and will not therefore be 

 referred to on this occasion. 



June 16th, 1909 u 



