92 REPORT — 1855. 



one or two instances of marine exuviae, as in a thin band of limestone near St. 

 Andrews, which contained fragments of minute encrinites ; but, taken as a whole, 

 the group was eminently characterized by freshwater estuary remains. The cha- 

 racteristic plants were Spheuopteris uffinis, bifida and linearis ; Lepidophyllum inter- 

 medium ; Pecopleris heterophyllum ; Neuropteris Loshii ; Calamites cannaformis ; 

 Lepidodendron elegans, selaginoides and gracilis ; Lepidostrohus variabilis and orna- 

 tus; Stigmaria ficoides and stellaris, with Sigillaria pachyderma, and another of more 

 slender and regular growth. Of the animal remains the most characteristic were 

 Cyprisfaba and punctata, which abounded in all the shales and limestones; Micro- 

 conchus carbonarius ; various Unionidse, sometimes forming whole bands of lime- 

 stone ; Palceoniscus Rohisonii, Eurynotus, and Ambhjptervs ; Holoptychius Hibbertii 

 (which was altogether different from the Holoptychius of the Old Red) ; Megalich- 

 ihys, Gyracanthus, and some other well-marked ichthyolites and coprolites. So 

 characteristic were many of these fossils, that there was little difficulty in deter- 

 mining by their aid the lower from the upper coal-measures. What Mr. Page 

 chiefly wished to establish by his lemarks, were, — 1st. That the limestone of Burdie 

 House was not a mere local and anomalous deposit, but had a considerable geogra- 

 phical range. 2nd. That its position was unmistakeably among the lower coal- 

 measures, and beneath the mountain or marine carboniferous limestone. 3rd. That, 

 in its palaeontological features, the Burdie House limestone is of undoubted fresh- 

 water or estuary origin ; and, 4th. That while the Burdie House limestone, per se, 

 was of estuary origin, as most of the lower coal-measures were, yet, in several 

 instances, bands of limestone and ironstone occurred in the series containing en- 

 crinital joints, Retepora, Murchisonia, and the like, thus showing that during the 

 deposition of the lower carboniferous strata there were occasional alternations of 

 marine and freshwater conditions. 



On the Subdivisions of the Paleozoic and Metamorphic Rocks of Scotland, 

 By D. Page. 



At the former meeting Mr. Page had endeavoured to establish, that below the carbo- 

 niferous limestone proper there existed in Scotland an extensive and well-defined group 

 which he termed the " lower coal-measures," and which were evidently the equiva- 

 lents of Mr. Griffith's " carboniferous slates " in Ireland. He had also endeavoured 

 to show that the yellow sandstones of Dura Den and Stratheden were a distinct 

 Devonian, or old red sandstone group, and clearly separable, lithologically and palaeon- 

 tologically, from the carboniferous system with which they were by some still con- 

 founded. He had during the past summer worked out numerous sections, both in 

 the north and south of Scotland, and now ventured to submit the following as well- 

 defined subdivisions of the palaeozoic and metamorphic strata. He omitted all notice, 

 in the meantime, of the Permian rocks and their supposed triassic co-relatives, 

 believing that these groups in Scotland had, as yet, been altogether misunderstood 

 and misinterpreted : — 



{Upper coal-measures. 

 Millstone-grit (feebly indicated). 

 Carboniferous limestone (marine). 

 Lower coal-measures. 

 {Yellow sandstone of Stratheden and Elgin. 

 Red sandstone and conglomerates. 

 Caithness flags and grelt conglomerate. 

 Forfar flags and tilestones. 

 r Undetermined zone. 



Silurian System -I Middle group of Ayrshire. 



L Lower group of Peebles and Roxburgh. 

 rClay-slate group. 

 ., T, J Chloritic and micaceous schist group. 



Metamorphic Rocks .^ Hornblende schist and quartzitic group. 



|_ Gneiss and granitoid schists. 

 Presuming that the preceding subdivisions of the carboniferous strata would now 



