Land, Fresh- Water, and Marine Crustacea. 273 



Achray; Loch Husky (Evans); and generally throughout the 

 district, especially in the smaller bodies of water. 



Objection is taken to the separation of this species from 

 the genus Cypridopsis, to which it was ascribed by Dr G. S. 

 Brady in 1867, but, as pointed out by Brady and Norman in 

 the Appendix to their valuable Monograph, pp. 725 and 726, 

 its removal became necessary when it was found to differ 

 materially in the principal character on which the genus 

 was founded, viz., the caudal rami. These were described 

 as " being quite rudimentary, consisting of two slender 

 setiform processes springing from a common base." Careful 

 examination has shown that while G. villosa, C aculeata, and 

 one or two others agree so far with this definition, the 

 caudal rami in C. vidua consists of four setiform processes, 

 and also that the basal part of each pair of processes differs 

 to some extent. Dr Kaufmann does not appear to attach 

 much value to this difference, and therefore replaces G. vidua 

 under Cypridopsis, but he at the same time removes the 

 others to a new genus — Cypridopsella — the chief distinguishing 

 character of which is that while the first has five the other 

 has only two hairs on the branchial plate of the first 

 maxilla. 1 Though C. vidua was made the type of the 

 genus Cypridopsis by Dr Brady, it was doubtless because 

 he considered its furca to be similar to that of the two 

 species associated with it, and as these two species agree 

 with the definition of Cypridopsis, I think they ought to be 

 retained in that genus, and C. vidua removed, as has been 

 done by Brady and Norman. 



G-enus (10) Potamocypris, G-. S. Brady, 1870. 



21. Potamocypris fulva, G. S. Brady. 



1868. Bairdia fulva, Brady, Mon. rec. Brit. Ostrac, p. 474, 

 pi. xxviii. fig. 21. 



Hob. — Duddingston Loch, Loch Leven, Eaith Lake, Loch 

 Gelly, and several other places. Ben Ledi, at 2500 feet 



(Evans). 



1 Cypridopsis — Branchial platte des Kiefer fusses mit fiinf Borsten. 



Furka verkiimmert mit geisselformiger Borste. 

 Cypridopsella — Branchial platte des Kiefer fusses mit zwei Borsten. 



Furke verkiimmert mit geisselformiger Borste. 



