306 Davidson — Earliest British Brachiopoda. 



with which wo arc at present acquainted ; and as it has been fully 

 described in my Silurian Monograph, all I would here repeat is that 

 it seems to have existed during the larger portion of the Middle and 

 Upper Lingula flags, and that it apparently disappeared at about the 

 termination of the ' Trcmadoc period.' I am not, however, satisfied 

 that the two incomplete specimens (PL XV. Fig. 9), found by Mr. 

 Belt in the upper division of his ' Maentwrog Group,' do really be- 

 long to the species under description. L. Davisii is very abundant 

 at Garth, Portmadoc, at Whitesand Bay, St. Davids, and in several 

 other localities. 



2. LiNGULELLA FERRUGiNEA., Salter. PL XV. Fig. 1-8. 



Lingulella unguiculus, Salter. Eeport of the British Association, 

 (p. 285), 1865 = L. ferruginea and L. ferruginea var. ovalis, 

 Salter. Quarterly Journal Geol. Soc. (Vol. xxiii. p. 340), 1867. 



This small species has been correctly described and illustrated by 

 Mr. Salter, and is, as far as we are aware, the earliest Brachiopod 

 hitherto discovered, for the specimens (PL XV. Fig. 2^-'^) were 

 found by Mr. Hicks at the very base of the purple and red rocks of 

 the Harlech Group of Sedgwick, which directly underlies the Mene- 

 vian Group or Lowest Lingula flags, ^ and where it does not appear 



^ " The little specimen kindly examined and pronounced by you (Mr. Davidson) to 

 be Linff. ferruginea was recently found by me at Portbclais Harbom-, near St. David's, 

 in one of the lowest beds belonging to the purple and red Cambrian rocks, exposed in 

 this neighbourhood — at the very base of a series looked upon as the equivalent of the 

 Harlech Group of Sedgwick and of the Upper Longmynds of Murchison, and directly 

 overlying olive green grits and shales like those of North Wales and Shropshire. 

 Its position, therefore, is about 1200 feet lower in the series than the specimen 

 described by Mr. Salter and myself in the Quarterly Journal of the Geol. Soc. 

 (vol. xxiii.), which was found, as there stated, in one of the red beds of the 

 upper part of the series ; and also about 900 feet lower than the fauna subse- 

 quently discovered by me in the intermediate beds, consisting of new species of 

 Conocoryphe, Faradoxides, Microdiscus, Theca, Agnostus, and Liscina. It is un- 

 doubtedly the earliest Brachiopod hitherto found : and it furnishes one of the first 

 unmistakable evidences, yet obtained (next to the minute Rliizopod F.ozoon), of so 

 very early an existence of animal life upon our globe ; lob-worms and fucoids claim, 

 no doubt, an equal antiquity, but they are not of so high a form of organization. The 

 Harlech fauna includes, in addition to the above-mentioned species of Conocoryphe, 

 Faradoxides^ etc., another trilobite {Palceopyge Ramsayi) found by Mr. Salter in the 

 Longmynds ; also the well-known Oldhamia, at Bray Head, These, inclusive, com- 

 prise all the fossils yet discovered in the enormous series intervening between the 

 Laurentian Rocks and the Menevian group." — (H. Hicks). 



In the Menevian Group,' along with L. ferruginea in addition to the other 

 Brachiopoda from the group to be described in this paper, the following fossils have 

 been found, namely: Faradoxides Favidis ; F. Ilicksii ; F. aurora; Conocoryphe 

 variolaris ; C. humerosa ; C. applanata ; C. hufo ; Microdiscm imnciatus ; Anopolenus 

 Salteri ; A. Henrici ; Frinnys {Harpides) venulosa ; IIolocep)halina primordialis ; 

 Agnostus Favidis ; A. Barrandii : A. Fskriggii ; Fcperditia solvemis ', L. vexata : 

 Frotospongia fenestrata ; F.Jlabellu ; F. diffusa : Froiocystites, S'p.; Theca corrugata ; 

 T. stillclto ; T. penult ima ; Stenotheca cornucopia ; Cyrtotheca hamula ; etc., etc. I 

 may also here remind the reader that it is interesting to notice how important 

 a.nd well-known this group has become within the last few years. In 1862 Mr. 

 Salter succeeded in finding fragments of Faradoxides and another Trilobite Micro- 

 discus in the rocks of St. David's, and these were the first indications obtained of the 

 presence of this fauna. In the following year Mr. Hicks succeeded in discovering no 

 fewer than forty new species in these beds; these now ibnu the great and well- 



