346 Prof. T. R. Jones on 
are two forms which have been called Z. alta (Conrad). 
These were figured by Prof. James Hall in the ‘ Paleon- 
tology of New York,’ 1852, and were described and figured 
by myself in the Ann. & Mag. Nat. Hist. 1856, ser. 2, 
vol. xvi. p. 88, pl. vil. figs. 6, 7; and 1858, ser. 3, vol. 1. p. 250, 
pl. x. figs. 8,9. Prof. Hall subsequently referred to these 
forms in the ‘ Paleontology of New York,’ vol. ii. 1859, 
part i. p. 372, intimating that the larger of the two might be 
distinguished as L. Jonesiz; but the illustrations were not 
published with the text. It seems to me, however, that these 
larger (higher) specimens should retain the specific name of 
altaen 
In the ‘ Report of the Geological Survey of Ohio,’ parti. 
Paleontology, 1873, p. 187, Prof. F. B. Meek redescribed 
L, alta (Conrad), and gave two outlines (pl. xvi. figs. 2, a, b), 
analogous to the earlier figures, of the broad and the narrow 
forms respectively. In this case, as in the others, the two 
shapes ought to be distinguished, fig. 2 6 (like fig. 7, pl. vil. 
Ann. & Mag. Nat. Hist. 1856) being a representative of L. 
phaseolus (His.) of Scandinavia; whilst fig. 2 a (like fig. 6, 
l. c.) is a broad or higher form, deserving the name “ alta.” 
10. Leperditia Hicksit, Jones. (Pl. XX. fig. 6.) 
Leperditia Hicksw, Jones, Quart. Journ. Geol. Soc. 1872, vol. xxviii. 
p. 183, pl. v. fig. 16 (mala), 
An incorrect figure (reversed and imperfect) of this Cam- 
brian Leperditia, interesting on account of its rarity and age, 
having been given in the Quart. Journ. Geol. Soc. above re- 
ferred to, the specimen is here redrawn. It is + inch long and 
pyritous. It was found at St. David’s, South Wales, in or 
about the zone of Paradoxides Hicks, rather below the 
middle part of the Menevian group. 
IsOCcHILINA, Jones. 
1858. Subgenus, Jones, Ann. & Mag. Nat. Hist. ser. 3, vol. i. p. 248. 
1870. Genus, Jones, Monthly Microsc. Journ. October 1870, pp. 187, 
191. 
1872. Genus, Barrande, Syst. Silur. Bohéme, parti, suppl. to vol. i. 
. 95. 
1873. Genus, Schmidt, Mém, Acad. Imp. Sci. St. Pétersh. sér. 7, vol. xxi. 
no. 2, pp. 9, 21. 
1. Isochilina punctata (Hichwald). (Pl. XIX. fig. 12.) 
1856. Leperditia marginata (Kutorga), Jones, Ann. & Mag. Nat. 
Hist. ser. 2, vol. xvii. p. 91, pl. vii. figs. 11-13. 
1860. Leperditia phaseolus, var. punctata, Kichw. 
1873. Isochilina punctata, Schmidt, Russ. sil. Leperd. pp. 10, 22, 
figs. 86, 37. 
