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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



shadowed forth the prolific flora of the Carboniferous epoch, which 

 in the British Islands numbers 82 genera and 330 species ; but the 

 Devonian, which preceded it, has, up to the present time, yielded 

 only 12 genera and 18 species. In America, however, about 95 

 genera and 160 species have been described through the researches 

 of Dr. Dawson, Lesquereux, Yanuxem, Hall, Hartt, &c, especially 

 the first-named author, who has devoted a long life to the eluci- 

 dation of the Devonian and Carboniferous flora of the American 

 region. 7 of the 12 British Devonian genera occur in America, 

 viz. Catamites, Lepidodendron, Psilopliyton, Sagenaria, Splieno- 

 pteris, Stigmaria, and Trichomanites ; but our ill-preserved speci- 

 mens scarcely admit of specific determination, in fact even their 

 affinities are often difficult to make out ; and the poverty of our 

 flora is clearly seen from the few species (18) occurring to illustrate 

 the 12 genera. On such slender evidence it is difficult to conceive 

 from what area our Devonian and Old Eed Sandstone flora was 

 derived ; whether migration took place from Central Europe or 

 America. The facies appears to be American rather than European, 

 this being the case with the Scotch and Irish floras, especially 

 through Psilopliyton, Palceopteris, and Sagenaria. 



The Lower Devonian (Lower Old Eed) has yielded 2 species, 

 Lepidodendron nothwn, Unger, and Psilopliyton Declienianum, Carr., 

 with coniferous remains from Caithness and Wick in Scotland. The 

 Middle Old Eed contains Caulopteris Peachii, Salt. ( = ? Psilopliyton 

 robustus, Dawson), and the two mentioned as occurring in the Lower 

 beds. The Upper Old Eed species (12) approach closely to the Car- 

 boniferous. 7 genera and 12 species range through the Upper divi- 

 sion — Adiantites 1 species, Galamites 1, Filiates 1, Sagenaria 5, 

 Sphenopteris 2, Trichomanites 1, and Knorria 1. Thus only 18 

 species occur in the widely extended and thickly developed deposits 

 of the Old Eed of Scotland, the Silurian Old Eed, and the rocks 

 of the Irish area. 



Protozoa. — Scyphia turbinata, Sphcerospongia tessellata, and 5 

 species of Stromatopora all occur in the Middle Devonian ; Cauno- 

 pora, Phillips, Sparsispongia, D'Orb., and Coscinopora of Goldfuss are 

 probably synonyms of Stromatopora. The Middle Devonian lime- 

 stones of Torquay and Newton Abbot abound in the ever-varying 

 forms of these incrusting Protozoa. The Devonian forms differ 

 essentially from the Wenlock and Ludlow species, the type in those 

 rocks being S. striatella, whereas the characteristic species in the 

 Middle Devonian are S. concentrica, Goldf., and S. placenta, Lonsd., 

 or the Caunopora of both Phillips and Lonsdale. No Protozoa occur 

 either in the Lower or Upper Devonian, being strictly confined to 

 the massive limestones of South and North Devon. S. placenta, S. 

 ramosa, and S. verticillata are strictly British. 



Actlxozoa (Actinoidea, Dana; Coralliaria, M.-Edw.). — Perhaps 

 during no period in the physical history of the British Islands have 

 we had such a remarkable assemblage of Actinozoa as that which 

 so essentially and specifically characterizes the Middle Devonian 

 rocks of South and North Devon. Out of the 24 known genera and 



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