62 MR. F. R. C, REED ON THE GENUS LICHAS. {[ Feb. 1902, 
[Mrroronicuas, Giirich, 1901 (Neues Jahrb. Beilage-Band xiv, p. 521)= Meto- 
pias, Kichwald. Type, M. Hiibneri, Kichwald. | 
Nurrainia, Eaton, 1832 (‘ Geol. Textbook’ 2nd ed. pp. 33, 34). The name 
was applied by Eaton to two specimens of trilobites which are now assigned 
to the genera Trinucleus and Homalonotus respectively, and therefore it 
falls to the ground. Portlock, however, in 1843 (‘ Rep. Geol. Londond’ 
p- 274, pl. iv, fig. 1 & pl. v, figs. 1-3) revived it as a generic designation for 
the species Lichas hibernicus (Portlock). M.Schinidt (1885, ‘ Rev. Ostbalt. 
Silur. Trilob.’ pt. 11, p. 29) places this species, as represented by the head- 
shie!d, in the group Platymetopus, to which it undoubiedly belongs. The 
pygidium which is generally attributed to this species is believed by 
M. Schmidt to belong to another group or subgenus. 
Oxcnotrcnas, Schmidt, 1885 (‘ Rev. Ostbalt. Silur. Trilob,’ pt, ii, Mém. Acad. 
Imp. Sci. St. Pétersb. vol. xxxili, no. 1, p.31). The type-species chosen by 
M. Schmidt unfortunately is Z. Boltoni (Bigsby), which had previously been 
selected as the type of Arctinurus by Castelnau in 1843 and of Platynotus 
by Conrad in 1838. This species, moreover, does not possess the glabellar 
characters of the Russian species which M. Schmidt associates with it, and 
therefore the type of Oncholichas must be considered to be the species 
LL. ornatus, Angelin, 1854 (‘ Pal. Seand.’ p. 72 & pl. xxxvii, figs. 7, 7a), 
which Schmidt takes as the second and European example of the group. 
[PLarororicnas, Gurich, 1901 (Neues Jahrb. Beilage-Band xiv, p. 522). Type, 
L. avus, Barr. (‘Syst. Sil. Boh. Suppl. vol. i, pp. 12-19 & pl. x).] . 
| PLaryiicnas, Girich, 1901 (op. cit. p.522). Type, Fl. margaritifera(Nieszkowski) 
in ‘ Mon. Trilob. Ostseeprov. Archiv f. Naturk. Liv-, Ehst-Kurlands, ser. 1, 
vol. i (1857) p. 568 & pl. i, fig. 15.] 
Piatymetorus, Angelin, 1854 (‘Pal. Scand.’ p. 73 & pl. xxxviii, fig. 3). Type, 
Pl. planifrons, Angelin (pars). XM. Schmidt (‘ Rev. Ostbalt. Silur. Trilob.’ 
pt. ii, 1885, pp. 28-29) considers PZ. lineatus, Angelin (‘ Pal. Seand.’ p- 75 
& pl. xxxvili, fig. l2 head-shield, now fig. 13 pygidium), to be the type, 
because P/. planifrons has been shown to be a composite type, the pygidium 
(fig. 8) being closely allied to that of L. (Dicranopeltis) scaber, Beyrich, 
while the hypostome alone (fig. 3a) belongs to the group of which 
Pl. lineatus (tig. 12. head-shield) is a member. [Dr. Girich (Neues Jahrb. 
Beilage-Band xiv, 1901, p. 624) takes Pl. Holme, Schunidt (‘ Rev. Ostbalt. . 
Silur. Trilob.’ pt. ii, 1885, p. 548 & pl. vi, fies. 14-17) as the type.|—The 
name Platymetopus, however, must be abandoned for this group, since it 
Was given previously in 1829 by Dejean to a genus of insects (‘Spéc. gén. 
Coléupt.’ vol. v, p. 815). 
Pratynotus, Conrad, 1838 (Rep. Geol. Surv. N.Y. pp. 113, 118). Type, PV. 
Boltont (Bigsby).--The name Platynotus was employed by J. C. Fabricius 
in 180L for a genus of Coleoptera (‘Syst. [leutherat.’ vol. 1, p. 188), and 
must therefore be discarded tor a group of trilobites. : 
[Prustarces, Girich, 1901 (Neues Jahrb. Beilage-Band xiv, p. 526)= Corydo- 
cephalus, Corda. ‘'ype, L. palmata, Barr. | 
Prerouicias, Girich, 1901 (op. cit. p. 525)=Arctinurus, Castelnau. Type, 
L. Boltoni (Bigsby). | 
Trratasris, Hall, 1863 (16th Ann. Rep. N.Y. State Cab. Nat. Hist. p. 223). 
Type, Z. grandis (Hall) 1861 (‘ Descrip. New Species of Fossils, ete.’ 15th 
Ann. Rep. N.Y. State Cab. Nat. Hist. p. 82). [For figures, see Hall & 
Clarke, Pal. N.Y. vol. vii, p. 73 & pls. xvii-xix.] 
[TRACRYLICHAS, Giirich, 1901 (Neues Jahrb. Beilage-Land xv, p. 525)= Di- 
cranopeltis, Corda. ‘Type, L. scubra, Beyrich. | 
= 
