40 CARBONIFEROUS LAMELLIBRANCH1ATA. 



De Koninck figured two shells of very different appearance in his first work, 

 18-13, and subsequently in 1885 re-described his shell under the name Aviculopect&n ? 

 dnpliciradiatus. The writer of the description of this shell states that de Koninck 

 confounded his species with that of Phillips, but that it differs in possessing 

 bifurcating radiating ribs. Now one of the few characters that Phillips's figure 

 does undoubtedly show, is that of having bifurcating radiating ribs. I have, 

 therefore, no hesitation in placing de Koninck's specific name as a synonym of 

 /'. simpler. I strongly suspect that Limalulina radula belongs to the same species. 



Phillips says of his species, " Upper valve, fig. 27, much flatter," but the figure 

 shows a comparatively gibbose shell. 



Pal.v.olima i,-i;vjs, sp. nov. Plate XIX, figs. 13 — 1 ( > . 



Specific Characters. — Shell small, slightly inequivalve, gibbose, ovate, oblique, 

 with lower part of the posterior margin produced. The anterior border rounded 

 and short, The posterior margin almost straight and very oblique. Hinge- 

 line straight, of moderate length. Umbones gibbose, pointed, placed almost 

 at the centre of the hinge-line. That of the left valve larger and more elevated 

 than that of the right valve. Ears very marked, narrow, the posterior the longer, 

 while the anterior is deeper. 



Interior. — Unknown. 



Exterior. — Surface smooth. Ears smooth. 



Dimensions. — PI. XIX, fig. 13, a right valve, measures — 



Antero-posteriorly . . . .14 mm. 



Dorso-ventrally . . . .13 mm. 



Locality. — Ireland: the Carboniferous Limestone of Little Island, co. Cork. 



Observations. — 1 cannot find any previous description of this little shell. In the 

 cabinet of Mr. J. Wright, of Belfast, there is a tablet of seven specimens which 

 have served for the description of the species. Two of them are right valves and the 

 others left valves. The oblique character of the shell and the overlapping of the 

 left umbo have induced me to place the species in the genus Palseolima. 



Pal eolima obliquikadiata, sp. nov. Plate XIX, figs. 17 — 10. 



Specific ( Characters. — Shell of moderate size, transversely oblique, oval, obliquely 

 gibbose, inequivalve, very inequilateral. Ears almost obsolete. The anterior 

 border ellipsoidal, the lower margin slightly convex in front, produced downwards 

 and more convex posteriorly. The posterior border almost straight, very oblique 



