CAMBRIAN SHALES NEAR CAERNARVON. 135 



not so numerous here as in the first place ; but Phyllopod crustaceans 

 appeared to predominate. 



The last place is on the same side of the river as the first, but 

 about three quarters of a mile higher up, close to the mill beloiu 

 Peblig Bridge, but on the opposite side of the river ; and the only 

 two specimens found were got out of the material taken from a pit 

 which was said to be sunk for the purpose of getting coal ! 



The rock here has quite a different texture from that of the formerly 

 described rocks, being finely laminated and without the jointed and 

 concretionary structure of the other rocks. It has a fine texture 

 and greasy feel. In it occur veins of quartz &c, which show most 

 beautiful instances of slickensides. The pieces in which the fossils 

 occur were got from a depth of about 60 feet from the surface. 

 Fossils seem to be scarcer here than at the other places. I only found 

 two pieces, one having on it a tube, and the other a tube similar to 

 the former on one side, and a Graptolite on the other. 



On the whole the first place has afforded a much greater variety 

 than the other two ; but as it was worked for a very much longer 

 time, it is doubtful whether, with thorough search, the second would 

 not yield a much more abundant fauna than it has hitherto done. 

 The third place seems to be much less fossiliferous than the other 

 two, the more so as, although I tried a fourth place about a quarter 

 of a mile higher up the river than the third, and on the same bank, 

 and although the shale was of exactly the same character as that of 

 the third place, it did not yield a sign of any organism whatever. 



The whole deposit is the more interesting as the only remains 

 hitherto found are a single specimen of Bellerophon perturbatus 

 below Penrhyn Park, near Bangor, some Graptolites and an obscure 

 fragment of a Crustacean near Caernarvon, at the place first described 

 in this paper. Cf. Prof. Ramsay's Memoir on the Geology of North 

 Wales (Mem. Geol. Survey, vol. iii. p. 161). 



The fossils seem to indicate that the deposit belongs to the upper 

 part of the Arenig group. 



Arr-ENDix. By Henry Hicks, Esq., F.G.S. 



In the interesting series of fossils collected by Mr. Marr, and which 

 have been placed in my hands for identification by Professor Hughes, 

 I have been able to recognize the following forms : — a new Caryocaris, 

 a new ^Eglina; Trinuclens, sp. ; Barrandea, sp.; Lingula, sp. ; Dis- 

 tinct, sp. ; Obolclla, sp.'; Orthoceras caereesiense (Hicks), Didymograptus 

 bifidus (Hall), D. indentus (Hall), D. MurcMsoni (Beck) and var. 

 furcillatus (Lapw.). The specimens hitherto discovered are for the 

 most part fragmentary; and hence identification of some of the species 

 is difficult. I have therefore preferred in such cases to note the 

 occurrence of the genus only. Others are undoubtedly new species 

 or varieties, to which I propose to give names, though I do not think 

 it would be advisable to figure or describe them fully until better spe- 

 cimens are found. Fortunately the species recognized enable us to make 



