CARBONIFEROUS FOSSILS OF IRELAND. 115 



This species is frequently confounded with the Producta hemispherica, but is wider, and usually more 

 depressed ; the large spines completely distinguish it from that species. 



Producta setosa. Phil. 



Producta setosa. Phil. Geol. York. 



Sp. Ch. — Subcylindrical, semicircular, very gibbous; ears flattened, distinct, rectangular; surface strongly 

 striated from the beaks ; irregularly spinous ; length and breadth equal. 



This species resembles the Producta sj)inosa, bvxt is much more distinctly striated ; the hinge-line is longer, 

 and the ears larger, and more distinct. Length three quarters of an inch. 



Probucta spinosa. Sow. 



Productus spinosus. Sow. Min. Con. 



Sp. Ch. — Rounded, very gibbous; obsoletely ribbed, longitudinally ; with very long, cylindrical spines; 

 hinge-line very short; no mesial furrow. 



This differs from all the nearly allied species in being marked by faint, rounded, smooth, radiating ribs ; 

 the spines, when well preserved, are perfectly cylindrical, and sometimes nearly two inches in length ; the hinge- 

 line is so short, that the back of the shell is much rounder than the front. Length nine lines, width eight lines. 



Producta spinulosa. Sow. 



Productus spinulosus. Soic. Min. Con. — Producta spiuulosa. Phil. Geol. York. 



Sp. Ch. — Semicircular, depressed, without mesial hollow; beak large, gibbous; surface smooth, ■with many 

 small spines. 



The ventral valve of this scarce little species is very concave ; the hinge-line is long and straight, the ears 

 square, flattened ; the beak is very large, inflated. Length six lines, width nine lines. 



Producta striata. Fischer, sp. 



Mytilus striatus. Fischer. Oryctol. Mos Pinna inflata. P^e'/. Geol. York. — Producta limseformis. De Buck. Mon-F rod. — 



Producta anomala. Sow. Min. Con. 



Sp. Ch. — Shell large, trigonal, very irregularly conic, depressed; surface with close, small, waving striae, 

 which are usually rounded, or slightly flattened. 



This curious shell seems to me to be the type of a new and peculiar genus ; in form and general habit it 

 certainly resembles Pinna very closely, in which genus Professor PhilUps has placed it, but is distinguished by 

 one valve being concave and the other convex. Fischer originally referred it to Mi/tilus, from which it dif- 

 fered in having one valve concave, and in wanting a hinge-line. Von Buch and Mr. Sowerby have filaced it 

 in Producta, from which it seems to differ in not being eared, and, in fact, entirely wanting the straight hinge- 

 line of that genus ; the small, narrow, pointed beaks, and general form, are at variance with the usual charac- 

 ters of the genus. 



The present species is very irregular in form, some specimens being almost cylindrical, while others are 

 almost as broad as long, and flattened; the striation is not subject to so much variation ; on most specimens the 

 striffi are smooth and rounded, but irregular in size ; they are all flexuous, but irregularly so. Length one foot, 

 width five inches. 



Producta subaculeata. March, and De Ver. 



Leptaena subaculeata. De Ver. Bui. Geol. See. dc Trans. 

 The specimens referred to tliis species only differ from the L. uculeata, in having the spines perpendi- 

 cular to the surface, instead of being adpressed, as in that species. They are less wide, and have rather fewer 

 spines than the P. r/rauidosus. 



