Additional Notes on South African Phyllopoda. 5 



distinctioD. The species of the genus Streptocephalus, like 

 those of other gymnostracous Phyllopoda, may be much more 

 easily distinguished, especially by thg very characteristic 

 structure of the prehensile antennæ of the male, partly also 

 by that of the caudal rami. I may add, that in all probability, 

 on a closer investigation, it will be found necessary to reduce 

 considerably the number of species established by different 

 authors, as it is easy to believe that the species in reality 

 have a much wider geographical distribution than formerly 

 opined, and that it is at any rate at present quite inadmissible 

 to believe that each continent must necessarily have its 

 peculiar phyllopodous fauna. Thus in later years it has been 

 stated that the very easily recognizable form, Cyclestheria 

 Hislojn (Baird) occurs in all the continents except Europe, 

 having been recorded from India, Ceylon, Celebes, Australia, 

 East Africa, Brazil. It is very probable that other Phyllo- 

 poda may also have a similar wide distribution, and that in 

 some instances forms previously regarded as distinct, chiefly 

 on account of their remote occurrence, may, on a closer 

 comparison, turn out to be in reality identical. But at 

 present it is scarcely possible to settle this question for 

 want of sufficiently exact and exhaustive descriptions and 

 figures of the species established. In order to facilitate 

 such a comparison in future, I have been anxious, in the 

 several papers published on these Crustacea, to give at least 

 good and easily recognizable figures of all the species 

 examined by me. 



