Prof. T. Rupert Jones — Fossil Bivaked Entomostraca. 105 



VI. — In the British Association Eeport for 1850, Transact. 

 Sections, pp. 79-81, Prof. Edward Forbes defined several species of 

 " Cyprides" as characteristic of the several divisions of the Purbeck 

 beds of Dorset. He did not publish figures of these forms ; but 

 from his diagrams, used at the Museum of Practical Geology, Sir C 

 Lyell had reduced figures drawn for his " Manual of Elementary 

 Geology," 3rd edition, 1851, p. 231. In the sixth edition of his 

 " Elements of Geology," 1865, they are thus given : — ■ 



p. 378, fig. 368, a. Cijpris gibbosa, E. Forbes. [Near C. spinigera, Sow.] 



b. tuberculata, E. Forbes. [Near C. tuberculata, Sow.] 



c. legimiinella, E. Forbes. 



These belong to the " Upper Purbecks." 



p. 378, fig. 371, a. Cijpris striatopunctata, E. Forbes. [? Fr. A. Eomer.] 



b. fasciculata, E. Forbes. 



c, granulata, E. Forbes. [? C. granulosa, Dunker.] 



These belong to the " Middle Purbecks." 



p. 387, fig. 375, a. Cypris PurbecJcensis, E. Forbes. 

 b. punctata, E. Forbes. 



Belonging to the "Lower Purbecks."^ 



In the Mem. Soc. phys. Hist. nat. Geneve, vol. xviii. part 1, 

 1865, MM. Loriol and Jaccard, in their " Etude geol.. etc., Villiers- 

 le-Lac," etc., notice an Ostracod as Cypris Furbeckensis, Forbes, p. 

 81, pi. 2, figs. 1 — 3 ; but it is difficult of determination on the small 

 figure given. 



VII. — By way of determining the specific identities or differences 

 of the above-quoted fossil Entomostraca, we may take the leading 

 characters of shape, and, especially the ante ro- ventral notch, and 

 group the named forms accordingly. Thus — 



!/ 1. Ovate- oblong, with strong notch (common 

 n rr jj ■ xi-i-j. ) foi'm ; Sowerbv's figured specimen). 



0. Valdenszs, Fitton. j ^ q^^' ^^^^^ ^^ ^f^^^^ ^^^^^ ^^^^^^^,^ 

 { figured specimen). 



— tuberculata. Sow. Oblong, without a notch. 

 — granulosa, Sow. Oblong, without a notch. 

 — spinigera. Sow. Oblong, with a slight notch. 



r C. Valdensis, Fitton. Ovate, with a strong notch. 



I — oblonga, R. Ovate (with a notch, according to Dunker). 

 Eceyner's j — striatopunctata, E. Ovate (with a notch, according to Dunker). 

 species. — \ — tuberculata, Fitton. Oblong, without a notch. 



[ — granulosa, Fitton. Oblong, without a notch. ("Without a notch 



\ according to Dunker.) 



1 In the " Catalogue of the Collection of Fossils in the Museum of Practical 

 Geology," 1865, p. 254, the following are enumerated: — 

 Cypridea fasciculata, \ 



punctata, I 



Valdensis, \ Middle Purbeck. 



Cypris striatopunctata, \ 



PurbecJcensis, J 



Cypridea tuberculata, ) jj p^^g^k. 



Valdensis, \ ^^ 



Some of these names have evidently been adopted from Forbes. 



