GLACIATION OF THE SHETLAND ISLES. 811 
APPENDIX. 
A lust of Fossil Plants, collected in Shetland, by Messrs. B. N. Peach 
and John Horne, of the Geological Survey, in 1878. 
By C. W. Pzacs, Esq. 
( Small specimens. In the Sandstone 
| quarries of Bressay and those on 
No. ite si 
1&1la. Calamites canneformis, from 4 ay Teice ree as EE 
5 Soi ba) 
Bressayeeeseeseeseec eee ree | known by the name of “‘ Corduroy” 
by the quarriers. 
( Unfortunately these are obscure; 
2. Lepidodendron nothum, Unger, | eee an ee 2 
! from Walls district............ they are what Salter called ZL. 
hi ” ” D2 Re nothum of Unger? They may be- 
5 ” ” EE eS long to Lepidodendron. I rather 
a ” ® ena 4 think they are nearer to Lycopo- 
2 ” 2 LOR dites Milleri, also figured by Salter. 
a ” ” EL | They have not stéqgmarian roots, 
a ” ” EG EIe but masses of long flat rootlets (the 
10, ” ” Rea as Fucoids of Miller and others). I 
i ” ” BD IEP got in, Caithness some of these, 
12, ” a es with splendid masses of rootlets 
: ” » aniie attached. 
1200, On the opposite side of 12, is a 
nice example of Psilophyton 
princeps of Dawson, showing 
leaflets. 
13. Psilophyton (from Noss). 
Th Pastonint : D This is the most abundant plant of 
Bagg eee ae ee eee UW BOD, the Old Red Sandstone of Shet- 
oe (from Walls) ..0.........-.--es land, Orkney, Caithness, &c. &e., 
ie. ” ” BR andiof Canada, America, and Tur- 
‘iS » ” dy one t key &e., in the Devonian of the 
’ ” ” ao latter countries. 
DiscussIon. 
Dr. Hicks, haying studied the adjoining rocks of the mainland of 
Scotland, differed from the authors as to the age of the metamorphic 
series, and thought they must be Pre-Cambrian, and belonging to 
two if not three Pre-Cambrian series. 
Prof. Bonnry asked as to the evidence of the passage of gabbro 
into serpentine. 
Mr. Hornz replied that they did not attempt in the paper to fix 
the age of the metamorphic rocks referred to by Mr. Hicks, and in- 
sisted on their views as to the intrusive character of the quartz- 
felsites of Shetland, 
In reply to Prof. Bonney, he stated that he and his fellow author 
had not minutely studied the supposed passage of one rock into the 
other, but that Dr. Heddle, who had so studied them, had aaeived 
at the same conclusion as themselves. : 
