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GEOLOGICAL MEMOIRS. 



citic plants are to be united to the Liassic flora, we must abandon 

 some of the most important results hitherto obtained. Every contri- 

 bution which may aid in clearing up these relations is of value. This 

 induces me to offer a list of the specimens, collected by Dr. A. Escher 

 von der Linth and Professor Merian in the Valais and in the Taren- 

 taise, and preserved in the Museums of Zurich and Basle, which I 

 have lately re-examined and compared with Coal-plants. I have 

 first a few general observations to offer. 



The question to be considered is this : — Do the belemnite- and the 

 plant-beds belong to the same formation or not ? If the former be 

 true, the question arises, — Is that formation to be regarded as Coal 

 from its plants, or as Lias from its Belemnites ? Brongniart, Bun- 

 bury, and Chamouset declare themselves of the first opinion, seeing 

 that the Belemnites are not specifically distinguishable, and that it is 

 by no means proved that the undoubted Lias beds containing Ammo- 

 nites belong to the Belemnitiferous series. E. de Beaumont, Sis- 

 monda, and Murchison take the latter view, since Belemnites have 

 never been found below the Lias, and because they think these beds 

 are inseparable from the ammonitic strata. These geologists found 

 their main argument on the position of the beds at Petit-Cceur. 

 Here the dark calcareous flags with the Belemnites repose on talcose 

 schists, and are in their turn covered by the schists containing the 

 plants. The belemnitic and anthracitic beds, says Murchison*, 

 form parts of the same group, the upper and lower members being 

 identical in composition ; and the talcose schists and the sandstones 

 being repeated. But this does not seem to me conclusive. In other 

 parts of the Alps, as in the Valais and the Col de Balme, the calca- 

 reous and the plant-bearing strata are seen to be separate, the latter 

 lying immediately on crystalline rocks : and even at Petit-Cceur the 

 belemnite- and plant-beds cannot possibly belong to one another. 

 Belemnites are acknowledged to have been marine animals, and they 

 must have been deposited on a sea-bottom. But neither in the Ta- 

 rentaise, in Savoy, in the Valais, nor in Styria, do the plant-bearing 

 schists contain the slightest trace of marine animals or marine vege- 

 tationf . The plants are all land-plants, and consequently, at the 

 time of their deposition, dry land must have been in the vicinity. 

 So perfect is the state of their preservation, — the most delicate pinnse 

 being still connected together, the tender Annularice and Asterophyl- 

 lites still with their perfect whorls of leaves united to their slender 

 stalks, the margins of the leaves seldom torn or damaged, and the 

 leaves so accurately spread out on the rock as if they were painted 

 on it, — that it is incredible that they can have been transported far. 

 They must therefore have grown in the neighbourhood. Let us sup- 

 pose that they grew on the margin of a sea in which Belemnites lived, 



* Loc cit. p. 176. 



t The Annularice and Asterophyllites alone are looked on by some (although I 

 think incorrectly) as aquatic plants ; still not as marine plants. These plants, 

 especially the Annularia fertilis, occur abundantly with and under the Ferns : they 

 probably lived in company with them under the shadow of tall trees, as do the 

 Asperuhse of the present time, to which they bear great resemblance. 



