344 



Harpax Terquemi ; j'ai cependant, reussi tout nouvellement a 

 mettre la main sur une valve droite, ou adlierente, en bon etat 

 de conservation, mais de petite taille." E. Dumoktier, Etudes 

 Palseontol. Ill^^^e partie, page 313. (Paris, 1869.) 



As the occurrence of this species is not only new to the 

 Cotteswolds, but also an addition to the British Liassic fauna, 

 it naaj be well moreover, to distinctly consider the bearing and 

 import of such additions as from time to time serve not merely 

 to enrich the fauna of a country ; but besides, tend to enlighten 

 our A'iew of the whole Jurassic period. 



These new forms of life teach us explicitly that the liassic 

 seas that surged and broke against that old reef of Montabart, 

 and filled its sinuosities with rare treasures of marine life, there 

 to be preserved for the delight of the palseontologist, was the 

 same water that was instrumental in depositing the several 

 strata of our Cotteswold Hills, and was obedient to the same 

 tidal wave that rolled over our western Islands, long before our 

 valleys were formed, or ever the Hills were made. 



And so to Geologists its import is clearly this, that there is 

 in the wide sense, no English Lias as apart from the Lias of 

 the North West Continent of Europe, but both series of deposits 

 are one, and in their unity are becoming more and more familiarly 

 known to the student as the Anglo-Parisian basin. Proofs of 

 this unity are continually multiplying, though really redundant 

 as proof; especially amongst the molluscan fauna of that basin. 

 Passing some of these under review, I will now mention just a few 

 that occur to us, belonging to this interesting group of forms ; 

 because they supply striking illustrations of the previous remarks. 

 How remarkable, for instance, is the Trigonia Lugdunensis, 

 from Langres in the deposits of the Ehone valley, the oldest 

 known true Trigonia* ; first discovered in this country by Prof. 

 Ealph Tate, (Geol, Magaz. 1872, p. 306) in the Middle Lias of 

 Cleveland, Yorkshire, in the Spinatus zone ; after that occurring 

 further south ; and lastly, found still further south by the late 

 Miss Baker, at Preston Capes, in Northampton. 



* See, Etudes Critiques siu- les Mollusques Fossiles, par L. Agassiz, Neuchatel, 

 La Suisse, page 2. 



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