28 PROF. T. R. JONES ON SOME PALEOZOIC OSTKACODA 



XI. Xestolebeeis, Sars, 1865. 



1. Xestolebeeis Wrightii, sp. nov. (PI. IV. figs. 14 & 15 a, h, c.) 



Length. Height. Thickness, 



mm. mm. mm. 



^^^^\ 15 1-2 -73 -8 



A Cytheroid Ostracod probably allied to the recent Xestoleberis, 

 see Ann. & Mag. Nat. Hist. ser. 5, vol. xviii. 188t), p. 264, pi. ix. 

 fig. 8. 



Carapace tumid, oviform, but more convex on one edge than the 

 other, and one valve much larger than the other ; both smooth. 



Named after Joseph Wright, Esq., P.G.S., of Belfast, who has 

 added much to our knowledge of fossil and recent Entomostraca. It 

 was obtained by him from the Lower-Silurian beds of the Chair of 

 Kildare, Leinster, Ireland, some years since. Eor some Cytheroid 

 and other Ostracoda sent from this locality by Mr. Baily and Mr. 

 Wright, see Ann. & Mag. N. H. ser. 4, vol. ii. 1868, pp. 54-62, pi. vii. 



[Addendum, December 18, 1889. — Since this paper was read the 

 following interesting specimens from North America, and collected 

 by himself, have been shown to me by Dr. G. J. Hinde, E.G.S. : — 



1. Several individuals oi Primitiopsis punctulifera (Hall), various 

 in their development and in the intensity of the reticulate surface- 

 ornament, from the Hamilton Group, at Thedford, Ontario. Also, 

 from the same formation at Eighteen-mile Creek, a small Strepu/a, 

 sp. nov. (?), and a small JSollia, near to, if not identical with, 

 B. bicolUna, J. & H. 



2. Schoharie, N. Y., Lower-Helderberg group : — Leperdltia alta 

 (Conrad) and L. Jonesi (?), Hall ; together with Kloedenia notata 

 (Hail). 



3. Arisaig, Nova Scotia, Lower-Helderberg group (C to D groups 

 of Honeyman) : — BeyricJiia pustulosa, Hall (casts), scarcely distin- 

 guishable from B. tuberculata, Boll ; and B. ceqiiilatera, Hall (casts), 

 scarcely separable from B. Kloedeni. 



4. Niagara Eormation, Dundas, Ontario ; small, simple Primitice, 

 flattened ; one has a minute tubercle at its sulcus. 



5. Cincinnati Eormation (Div. G of Billings), English Head, 

 Anticosti : — Numerous Ostracoda on thin limestone, some like 

 Bairdia, probably sp. nov. 



6. Clinton or Niagara Eormation, Division 2 of Anticosti Group, 

 W. of Jupiter Eiver, Anticosti : — a fringed Primitia^ sp. nov. ? 



7. Cincinnati Eormation, Group 1 of Billings, S. of Junction Cliff, 

 Anticosti : — several minute Ostracoda attached to small fossils ; some 

 probably spp. nov.] 



