
TRANSACTIONS OF THE SECTIONS. 57 
sider as belonging to the “Etage C,” may be cited the following fossils and 
localities :— 
PuLants. 
Species. | Localities. 
Chondrites, — sp. ...-..e. | Records Mus. Pract. Geol., | Carnedd Ffiliast, a moun- 
“i ined. tain 5 m. S.E. of Bangor. 
Cruziana semiplicata, n.sp. | Salter, ibid. ..........cceseeee Ditto (specimensmore than 
a foot long, abundant). 
Crustacea. 
Olenus micrurus....... ess. | Salter, Decade 2. pl. 10. of | Dolgelly; Trawsfynydd; 
Memoirs Geol. Survey. Tremadoc; N.W. of 
Llanberis. 
Hymenocaris vermicauda, | Salter, Records Mus. Pract. | Dolgelly; Tremadoc ; Pont 
new genus. Geol., ined. Seiont, Caernarvon ? 
Mo.tuvsca. 
Lingula Davisit. ......06004 M‘Coy, Ann. and Mag. | Dolgelly; Tremadoc; N.W. 
Nat. Hist. vol. viii. 405. of Llanberis; Carnedd 
Ffiliast; near St. Ann’s 
Chapel, Bangor; &c. 
One of the most interesting fossils is a large Paradowides, probably P. Forchham- 
meri, Angelin; but most unfortunately the exact locality in North Wales has not 
been preserved, though there is great probability it comes from the ‘ Lingula Flags.’ 
In the higher beds, near the upper limit of the igneous series, Prof. Sedgwick and 
myself gathered in 1843 the following fossils. 
| Asaphus Selwynii, n. sp. . | Salter, Records Mus. Pract. | Hengwrt uchaf, 4m. N.E. 
Geol. ined. of Dolgelly,a bed of slate 
in the volcanic ash. 
Calymene parvifrons. ...... | Salter, Append. to Prof. | Tai hirion, under, the trap 
M’Coy’s Paleozoic Foss. and volcanic ash-beds of 
Woodw. Mus. pl. 1. F. Arenig bach. 
frie 
Lingula Davisti?...iccssceee | M‘Coy, supra. sissccsscereee Tai hirion; and Llyn-y-Dy- 
warchen, to the west of it. 
The Geol. Surveyors have 
also found Lingule at 
Hengwrt uchaf. 
Lastly, at Llanfaelrhys near Aberdaron, South Caernarvonshire, in beds which both 
by position and mineral character appear to be the ‘ Lingula Flags,’ although sepa- 
rated by great dislocations and obscured by drift, the following fossils occur. 
Asaphus Selwynii, n. sp., mentioned before. 
Lingula attenuata? 
, broader species. : 
Didymograpsus Murchisone, an 
Graptolites incisus? or a new species. 
In all these, except the first list, some doubt may be entertained whether the strata 
may not more properly be classed with the second division, the ‘etage D’ of M. de 
Barrande. ‘The genera Asaphus and Calymene certainly would indicate it. There 
is every reason to believe that the Asaphus Selwynii is the same species as one common 
in the lowest Llandeilo flags of Shelve in Shropshire, and as such it is considered. 
Therefore, if the zoological demarcations, which are of so much value elsewhere, 
hold good in England, i¢ would be proper to draw the line between the fossils which 
occur at the base, and those near the top of the igneous series. 
__ Professor Phillips has described a formation of black shales occurring at the base 
of the Silurian series in the Malvern Hills, which is characterized only by small Tri- 
lobites, and these of the genera Olenus and Agnostus; they are Olenus humilis, Phill. 
Mem. Geol. Sury, vol. ii. pt. 1. p. 55. f. 4-6; 0. bisulcatus, Ph. f.1,2; O. scara- 

