New and Rare Fossils. 45- 



wise fairly smooth, excepting for a few striae pai'allel with tlie 

 ventral and anterior margins. 



Dimetisiom. — Length, .6.*U mm. ; height, .:J4G mm. ; thickness of 

 carapace, .308 mm. 



Affi/itfies. — The above species resemljles a weak form of Cytherura 

 ruditi, G. S. Brady, ^ that is, having minute pittings instead 

 of polygonal excavations, and without the faint flexuous ribs of that 

 species. The marked distinction of Ciiilwruni i)tnit'nen>si>i in having 

 a more rounded contour separates it from Brady's living species. 

 which came from the Arctic Seas and, doubtfully, from the Straits 

 of Magellan. Since Brady's recorded occurrence, ('. riulis has been 

 found by tjie writer in soundings from the Antarctic taken by 

 Capt. J. K. Davis in the " Nimrod " (British Antarctic Expedition, 

 1907-9). That specimen also showed a polygonal rather than the 

 punctate ornament of the present species. 



Occurrence. — Bore 11, 267-270 feet (Janjukian). 



, Genus CYTHEROPTERON. G. 0. Sars. 

 Cytheropteron batesfokdiense, Chapman. (Plate VIII., Fig. 36). 



Gytheropteroii hatesfordiense, Chapman, 1910, Proc. Roy. 



Soc, Vict., vol. xxii. (N.S.), pt. ii., p. 300, pi. ii., figs. 

 la-c. 



Ohner vat ions. — Since the discovery of the originally described 

 specimens in the Batesford Limestone, this species has been found 

 in some abundance in the lower strata of the Mallee bores. 



In the original description, I noticed the relationship of this- 

 form with Cytheropteron wellingtoniense, Brady. There is still 

 another species showing close affinities which occurs fossil in the 

 Cretaceous of Basdorf in Mecklenburg, namely, C. triangulares 

 Reuss sp.2, a species which also occurs in the Cainuzoic (London 

 Clay) of Copenhagen Fields and Piccadilly, London. This species 

 differs in having the alae less salient posteriorly, otherwise, as seen 

 in edge view, the two forms are very similar. 



Occurrence.— Bovi^ 2, 211-240 feet (Janjukian). Bore 10, 310- 

 320 feet (Kalimnan or Janjukian). Bore 11, 438-440 feet; 440-442 

 feetj 442-444 feet; 444-446 feet; 457-458 feet; 5-18-550 feet (Jan- 

 jukian). 



1. Ann. Mag-. Nat. Hist., ser. 4, vol. ii., 1868, p. 84, pi. v., fi-s. 15-17. Hep. ('hall. Zool., vol. i., 

 pt. iii., 1880, p. 1.52, pi. xxxii., flg.s. 3a-rf. 



2. Cijthere triangularis, Reuss, Zeitsc^hr. rl. deutseh. Gesellscli., vol. vii., ISu.t, p. 27i), pi. .\- 

 fig. 8. Jones, Men. Tert. Eritom. (Pal. Soc), 18.o7, p. 25, pi. vii., fig-. 5. Cytheroptenni. t) iaixjulure 

 Jones, Mon. Tert. Entoni. (Pal. Soc), 1889, p. 44, pi. ii., figs, \9a-c. 



