DEVONIAN. 235 



The view that Psilophylon does not exist as a true genus, but that its 

 larger branches belong to a Ltpidodendron, and its supposed fruiting branches 

 to a fern, I cannot admit.* 



The genus Psilophyton contains a very distinct group of Lycopods, whose 

 fruit clearly prohibits it from being united with any other genus of plants. 



The fossil named Psilophyton condrusorum by Crepin,f does not, I believe, 

 belong to Dawson's genus Psilophyton, and this view has already been adapted 

 by Crepin himself, who has constituted the genus Rhacophyton for his 

 Psilophyton condrusorum. 



Feistmantel figures two specimens in his " Das Kohlenkalkvorkommen bei 

 Rothwaltersdorf in der Grafschaft Glatz,"| which he refers to Psilophyton 

 robustius. His two fossils do not appear to belong to the genus Psilophyton, 

 nor even to the Lycopodiacece, but most probably to Stur's Calymmatotheca. 



I have examined the specimen described as Caulopteris ? Peachii, by SaJter 

 (Quart. Journ. Geol. Soc. vol. xv. p. 408, fig. 14a). It does not seem to belong 

 to the Ftticacew, but is, I am much more inclined to think, a large stem of 

 Psilophyton Dechenianus. 



Among the specimens in the Collection, and also in the Museum of Science 

 and Art, Edinburgh, are examples which show intermediate stages between 

 this specimen and others of undoubted Psilophyton Dechenianus. Caulopteris 

 ? Peachii cannot at all events be the trunk of Palceopteris Hibernica as 

 suggested by Schimper, for that fern does not, to my knowledge, occur in 

 any of the localities from which Psilophyton Dechenianus has yet been 

 collected. 



As I am not, however, in a position to affirm positively what is the true 

 nature of Caulopteris ? Peachii, a number of large stems, which in some 

 respects resemble it, though most probably belonging to Psilophyton 

 Dechenianus, are placed in this Catalogue under the head of " stems." 

 Horizon. Lower Devonian (Old Red Sandstone). 



Localities. -British. Banffshire : Gamrie. Caithness : Ackergill Castle, 

 near Wick ; Alrig Quarry ; Devil's Punch Bowl, 

 Island of Stroma ; East Mey, Barrogill Castle ; 

 Howland, near Wick ; John O'Groats ; Kilmster, 

 near Wick ; St. John's Point, near Mey Castle ; Stone 

 Gun Quarry, near Thurso ; Southhead, near Wick. 

 Forfarshire : Turin Quarry. Orkney : Dale Quarry, 

 Stromness. Shetland : near Lerwick. 



Foreign* New Brunswick : Campbellton, P. robustius, Dawson 

 (Presented by Sir J. W. Dawson). 



ARTHROSTIGMA, Dawson, 1871. 

 Foss. Plants, Devon, and Upper Sil. Form, of Canada, pt. i. p. 41. 



Arthrostigma gracile, Dawson. 



Arthrostigma gracile. 



Dawsou, Foss. Plants, Devon, and Upper Sil. Form, of Canada, pt. i. 



p. 41, pi. xiii., pt. ii. p. 104, pi. xxiv. fig. 22. 

 whimper, Traite d. PalSont. Veget. vol. iii. p. > 



Schimper, Traite d. Paleont. Veget. vol. iii. p. 549. 



Horizon. Middle Devonian. 



Locality. Foreign. New Brunswick : St. John's (Presented by Sir 

 J. W. Dawson). 



* See Crepin, los. cit. p. 13. 



t Bull. 1'Acad. E. Belgique, 2 e ser. vol. xxxviii, Aug., 1874. 



I Zeitsch. d. deut. Geol. Gesell. vol. xv. p. 541, pi. 18, figs. 39, 40. 



Traite d. Paleont, Veget. vol. iii. p. 527. 



