Eniomosfruca from Egypt and the Soudan. 31 



prominence of the preanal angle, the very regularly placed 

 postanal denticles (fig. 6), and the shorter and broader post- 

 abdomen. The latter difference is, perhaps, attributable to 

 immaturity, but the remains are too incomplete for satis- 

 factory identification. 



C O P E P O P A. 



(23) Diaptomus galebi, Barrois. 



In pools in the Zoological Gardens at Cairo, at Lecht, and 

 bv the Pyramids; abundant. Also found in the Blue and 

 the White Nile. 



(24) Diaptomus alluaudi, De Guerne & Richard. 



Pools by the road to the Pyramids, Sakkara, Lecht, 

 Dahchour ; a common species. A few specimens were also 

 found in the Birket el Kurun, but it is evidently not common 

 there. 



(25) Diaptomus salinus, Daday. 



Only found in the Birket el Kuruu, where, with Moina 

 salinarum, it forms the bulk of the plankton. 



My specimens agree in almost all respects with the 

 descriptions of Schmeil and others and with specimens from 

 Algeria, but they differ in the shape of the last thoracic 

 segment and the first abdominal segment of the female. 

 The last thoracic segment is scarcely at all produced into 

 " wings,'^ being simply rounded behind on the left side and 

 armed with two small spines, while on the right side it is 

 produced into a short outwardly directed point. The first 

 abdominal segment is very short and slightly asymmetrical, 

 the spine on the left side being larger than that on the 

 right. The proportional lengths of the furca and the abdo- 

 minal segments are, on an average, as follows : — 



Abdominal seg-ments. 



( '■^ ,, Furca. 



1. 2. 3. 



Length 13 5 8 11 



(26) Cyclops leuckarti, Clau-:. 



Abydos, near the Pyramids, Sakkara, White Nile, and 

 Blue Nile. 



