238 rossir, PLANTS 



INCERT^E SEDIS. 



PROTOTAXITES, Dawson, 1859. 

 Quart. Journ. Geol. Soc. vol. xv. p. 484. 



Prototaxites Logani, Dawson. 



Prototaxites Logani. 



Dawson, Quart. Journ. Geol. Soc. vol. xv. p. 484. 



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

 p. 16, pi. ii. figs. 18-27, pt. ii. p. 107. 



Nematophycus Logani. 



Carruthers, Monthly Micro. Journ., 1872, vol. viii. p. 160, pis. xxxi., xxxii. 

 Horizon. Upper Devonian. 



Locality. Foreign. Canada : Dalhousie, Province of Quebec (Presented 

 by Sir J. W. Dawson). 



STEMS. 



Remarks. Under this heading are placed the stems referred to in the notes 

 appended to Psilophyton Dechenianus* They may belong to more than one 

 species, but they do not show any characters by which they can be separated 

 from each other. Some similar examples have been figured and described 

 by Mr. Salter as " Coniferous Wood " t and " Flattened Boots." J On 

 several of the specimens the vegetable matter is converted into bright coal. 

 They occurred in company with Psilophyton Dechenianus. 

 Horizon. Old Red Sandstone. 



Localities. British. Caithness : Ackergill Castle, near Wick ; Borgie 

 Quarry, Olrig ; near Barrogill, Castle ; Castlehill ; 

 Gallowshill, near Thurso ; John O'Groats ; Stone 

 Gun Quarry, near Thurso. Dunscansbay ; Wydale, 

 near Thurso. Forfarshire : Turin Quarry. 



STEM. 



Remarks. This example may perhaps belong to Unger's Stereocalamece.^ 



Salter describes similar stems to that included here as having their surface 

 pretty regularly fluted by delicate longitudinal ridges, the intervening hollows 

 being gently concave, not abruptly grooved ; these ridges are tolerably 

 regular and equidistant, without being absolutely continuous ; seldom as 

 much as a line apart, but occasionally more. They are not interrupted by 

 any transverse joints as in Calamites.\\ 



Horizon. Old Eed Sandstone. 



Locality. British. Shetland : Lerwick. 



SPOROCHNUS, Stur (? non Kutzing), 1881. 

 Sitzb. k. Akad. Wissensch. vol. Ixxxiv. abth. i. p. 342. 



P Sporochnus, sp. 



See Stur, Die Silur.-Flora der Etage H-h., in Bohmen, loc. cit. 1881, p. 330. 

 Remarks. -The fossil placed here has considerable similarity with Spo- 

 rochnus Krejcii, Stur. The specimen has very much the appearance of a root 



* See ante, p. 235. 



t Quart. Journ. Greo. Soc. vol. xiv. p. 72, pi. v. fig. 2, and vol XT p 407 fie 6 

 t Ibid. vol. xv. p. 407, fig. 5. 



Kichter and Unger, Beitrag zur Palseontologie des Thiiringer Waldee. p. 181, 

 pi. xiii. figs. 3-11. 



|| Quart. Journ. Geol. Soc. vol. xiv. p. 73, pi. v. fig. 1. 



