PART II. 



The Table given at pages 2 and 3 of Part I (1888) indicates that bivalved 

 forms with the carapace-valves more or less easily separable, and either pod- 

 shaped or conchiferoid, come near to Geratiocaris lately described in that Part. 

 Some of these we shall deal with presently. There is one form, however, having 

 a folded shield, like that of Nehalia, which has the lateral halves of the carapace 

 and the exserted abdominal segments so much like those features in Geratiocaris 

 that it seems advisable to take it {Hipnenocaris) into consideration at once. We 

 may here remark that, with regard to the two associates of Hijinenocnris in the 

 Table at page 2, we have not yet obtained any further information about Barrande's 

 " Cytheropsis testis "^ and that Proncans (wrongly referred to this group as Proto- 

 caris) is not a Phyllopod, but had been conjecturally made up of portions of the limbs 

 of Euryfterus or Pterygotus. (See 'Report Brit. Assoc' for 1889 (1890), p. 68.) 



It will be convenient to take up in succession to Hymenocaris those forms 

 {Lingnlocaris, &c.) resembling the shells of some bivalve molluscs, and then the 

 little pod-like Caryocaris, which is probably not far removed zoologically from 

 Geratiocaris. Subsequently those with flat sutured carapaces {ApfycJiopsis, 

 Peltoearis, and Pinnocaris) will be described, and then such as have flat entire 

 carapaces (Discinocaris) ; and, lastly, the Apus-like forms {Dithyrocaris). 



A. Phyllopodous Forms with Hinged or Folded Valoe-like Garapaces. 



V. Genus — Hymengcaeis, Salter, 1853. 



Saltee, 'Eeport British Assoc' for 1852 (1853), Transact. Sect., pp. 56—58. 

 MoREis, ' Catal. Brit. Foss.,' 1854, p. 109. 



H. WooDWAED and Salter, ' Catal. and Chart Poss. Crust.,' 1865, p. 17. 



Salter, ' Memoirs Geol. Survey Great Britain, &c.,' vol. iii, 1866, p. 293 ; 2nd edit., 1881, 

 p. 484. 



1 The form quoted as such by MM. de Tromelin and Lebesconte in 1875 is not the same (see 

 Dr. C. Barrois's " Memoire sur la Faune du Gres Armoricain," ' Annales Soc. Geol. du Nord,' 

 vol. xix, 1891, pp. 147 and 149). 



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