174 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 7, 



smaller rib between the larger ones, the whole being closely inter- 

 sected by fine concentric lines, thus giving to the longitudinal ribs a 

 crenulated appearance. Prof, de Koninck coincides in my identifi- 

 cation. 



Productus. 



Although Sir C. Lyell and Dr. Dawson mention seven species of 

 this genus as having been found in the Lower Carboniferous rocks of 

 Nova Scotia, all these, as well as the specimens I have been able to 

 examine, can be referred to two species only, namely P. semireticu- 

 latus and P. Cora ; and I may mention that Prof, de Koninck coin- 

 cides in this view. 



13. Productus semireticulatus, Martin. PL IX. figs. 20, 21. 



Anomites semireticulatus, Martin, Petrif. Derb. pi. 32. figs. 1, 2, 

 and pi. 33. fig. 4, 1809. 



This species is so well known, that all I shall require to state is, 

 that the Nova-Scotian specimens are exactly similar to those found in 

 Europe. Producta Martini, P. concinna, P. antiquata, P. Scotica, 

 mentioned by Sir C. Lyell at p. 220 (vol. ii.) of his ' Travels in 

 America,' as well as by Dr. Dawson in various pages of his * Aca- 

 dian Geology,' belong to a single species, namely Productus semireti- 

 culatus, Sow. The " P. spinosa, Sow. ? var. of P. Martini" of Sir 

 C. Lyell's list, belongs likewise to the species under description ; but 

 P. spinosa, Sow., specimens of which I have not seen from Nova 

 Scotia, is a distinct species. Sir C. Lyell mentions Windsor, Brook- 

 field, Shubenacadie, East Eiver, Debert River, and Minudie. Dr. 

 Dawson states that the shell is found almost everywhere, at Pug- 

 wash, near Amherst, Boulardarie, Cape Breton, Horton Bluff, Gray's 

 Eiver, &c. 



The largest specimen measured one inch and a half in length by 

 about the same in width. The variety Martini is also found in the 

 same locality. 



14. Productus Cora, D'Orbigny, 1842. PL IX. figs. 22, 23. 

 Productus Cora, D'Orbigny, Paleont. du Voyage dans l'Amerique 



Merid. p. 55, pi. 5. figs. 8, 9, 10, 1842. 



P. comoides and P. Scoticus, De Kon. 1843 (not of Sow.). 



Producta corrugata, M'Coy, Synopsis of the Carb. Limest. Fossils 

 of Ireland, pi. 26. fig. 13, 1844. 



P. Lyelli, De Yerneuil, Sir Charles Lyell's Travels in North 

 America, vol. ii. p. 221, 1845. 



P. tenuistriata and P. Neffedievi, De Tern., Russia and the Ural 

 Mountains, 1845. 



P. Cora, De Koninck, Mon. du Genre Productus, pi. 4. fig. 1, 1847. 



P. pileifomiis, M'Chesney, Descr. of New Species of Fossils from 

 the Palaeozoic Rocks of the Western States of America, p. 40, 1849. 



P. Lyelli, Dawson, Acadian Geology, p. 219, fig. 9, 1855. 



P. Cora, Dav., Mon. Carb. Brach. pi. 36. fig. 4, pi. 42. fig. 9, 

 1861. 



After a very careful examination of nine or ten specimens of P. 



