CARBONIFEROUS FOSSILS OF IRELAND. 107 



Productus antiquatus, and by M. Deshayes, under that o{ Froducta lobata, to which latter shell it only bears 

 the most remote resemblance. As yet I am not acquainted with a figure of the adult shell, such as it usually 

 occurs in our limestone. Professor Phillijjs' figure represents a curious varietj', a specimen similar to which I 

 liave seen from the limestone of Cornacarrow, near Enniskillen, it is cylindi'ical, without mesial hollow, or large 

 concentric wrinkles, and with a considerable smooth space between each of the radiating striae ; altogether it has a 

 peculiar appearance, and may possibly be distinct. Length usually about three inches. Martin's name should, 

 perhaps, be adopted for the species, as having the priority, but Mr. Sowerby's name is so well known, that I 

 have thought it better to retain it. 



Producta aurita. Phil. 



Professor Phillips proposes this name for the P. hemispherica and P. Scotica of Sowerby, united. I have 

 occasionally used the name for a few specimens which have occurred, resembling P. Scotica, but with very few 

 spines, and ha\ang the ears unusually long. 



Producta caperata. Sow. sp. 



Lepta?na caperata. Soic. Geol. Trans Leptcena caperata. Phil. Pal. Fos. 



Sp. Ch. — Hemispherical, very convex, no mesial hollow; concentrically wrinkled; surface with small, 

 very numerous, oblong, tubercles arranged in quincunx ; ears transversely wrinkled. 



This species differs from the Producta scabricula in being much more convex, and more nearly orbicular 

 in its outline ; it has no trace of mesial furrow, the concentric wrinkles are stronger, and the tubercles smaller 

 and much more numerous than those of tlie Producta scabricula ; when well preserved, there are long, slender 

 spines on the hinge-line. Length one and a half inches, width two inches, depth ten Knes. 



Producta comoides. Sow. 



Productus comoides. Sow. Min. Con. 



Sp. Ch. — Semicircular, very gibbous, inflated; hinge-line equal to the width of the shell, cardinal area 

 wide, with nearly parallel sides ; shell very thick ; surface with very fine, waved, radiating strias. 



I am not sure that I by any means understand this species : the very large shell which I have been in the 

 habit of considering as P. comoides, I have recently been inclined to consider as the adult state of Professor 

 Phillips' O . papilionacea ; they agree perfectly, however, with Sowerby's figure and definition of his P. co- 

 moides, with the exception, perhaps, of the cardinal area not having such parallel sides : on the other hand, 

 specimens of a shell given me by Lady Peschel present a cardinal area with truly parallel sides, a very thick 

 shell, and similar form, but it is very coarsely sulcated, and possesses a hinge distinct from either Producta or 

 Orthis. Professor Phillips and M. de Koninck have, I think, figured a distinct species under this name. 



Producta concinna. Sow. 



Productus concinnus. Sow. Min. Con Producta conciiina. Phil. Geol. York. 



Sp. Ch. — Subcylindi-ical, very short, rounded, front evenly convex; surface coarsely striated longitudinally, 

 concentrically wrinkled near the beak. Length and width equal. 



This Httle species bears a great resemblance to the top, or rostral portion of the Producta Martini, it is, 

 however, much smaller, more rounded, and the surface more evenly formed ; the top of the ventral valve fre- 

 quently has a distinct, nearly smooth margin, as in that species. Length seven Hues, width six lines. 



Producta corrugata. M'Coy. (PI. XX. fig. 13). 



Sp. Ch. — Hemispherical, the concavity of the ventral valve nearly equalHng the convexity of the dorsal ; 

 radiating stri» narrow, sharply defined, alternately larger and smaller ; four or five large wrinkles on each side. 



