. 
G. J. Williams—Parys Mountain, Anglesey. 149 
graptolites, existing between the two principal hard bands of the 
Parys Mountain, but no list of species is given. 
Professor McKenny Hughes, in his second paper on the Geology of 
Anglesey, refers to ‘‘the black shales between the two great felsite 
ribs” in the Mona Mines of the Parys Mountain as the highest 
horizon from which he had procured any fossils! The late 
Mr. Fanning Evans, while searching for fossils in Prof. Hughes’ 
company, ‘‘had the good luck to pick up a slab containing no less 
than eight species of graptolites,” of which a list is given, but this 
appears to have been the only fossiliferous piece discovered. 
On several occasions during the last dozen years I have searched 
for fossils in the shales, but succeeded in obtaining none other than 
obscure traces till January of last year, when I discovered a number of 
Llandovery species, and I found others during a visit in the month of 
May. At this time a tunnel was being driven south in a part of the 
Mona Mine, between the two ‘‘ribs’’ mentioned above, and it is from 
this tunnel that the graptolites were obtained. The beds in the 
tunnel, which is now about sixty yards long, dip generally at an 
angle of about 45° north, though there occur some contortions and 
faults. The rocks consist of soft earthy shales, more sandy beds, and 
a few lenticular bands of a fine-grained, extremely hard rock. In the 
softer beds the graptolites are but indifferently preserved, while from 
the more sandy ones many specimens were obtained beautifully pre- 
served in relief. The following is a list of the species which were 
kindly named for me by Miss Elles, D.Sc. :— 
Cephalograptus cometa, Gein. 
Climacograptus Tornguisti, Elles & Wood. 
Climacograptus sp. ? 
Diplograptus tamariscus, Nich. 
D. sinuatus, Nich. 
M. involutus, Lapw. 
M. jaculum, Lapw. 
MM. leptotheca, Lapw. 
MM. lobiferus, McCoy. 
M. aff. cyphus, Lapw. 
+) be) 
Monograptus Becki, Lapw. 
M. Clingani, Carr. 
IM. communis, Lapw. 
M. convolutus, His. 
Miss Elles determines the zone as that of Monograptus convolutus 
(His.), just below the zone of I. Sedgwickii (Portl.). 
Last August my friend Mr. Edward Greenly, F.G.S., who, as is 
well known, is making an exhaustive survey of the geology of 
Anglesey, collected specimens which came from the same tunnel, but 
farther south, and he kindly allows me to publish a list of the species 
he obtained, and which, like mine, were named by Miss Elles. They 
are the following :— 
Climacograptus scalaris, His. M. intermedius, Lapw. 
Monograptus discretus, Nich. MUM. Sedgwickii, Portl. 
and one if not two species of Diplograptus which Miss Elles regards 
as new, and which will be described in the ‘‘ Monograph of British 
Graptolites.” Mr. Greenly’s specimens are from a slightly higher 
horizon than mine, viz. that of IZ. Sedgwickit, so that in the beds cut 
through in the tunnel the dip is inverted or there is a downthrow to 
the south. 
50 3 var. ambiguus, Tornq. 
Petalograptus minor, Elles. 
P. palmeus, var. latus, Barr. 
' T. McKenny Hughes, ‘‘ On the Geology of Anglesey,’? No. 2: 
Q.J.G.8., 
vol. xxxviii (1882), p. 27. 
