THE ANNALS 



AND 



MAGAZINE OF NATURAL HISTORY. 



. [SECOND SERIES.] 



«« per litora spargite museum. 



Naiades, et circdm vitreos considite fontes : 

 PoUice virgineo teneros hic carpite floras : 

 Floribus et pictum, divs, replete canistrum. 

 At vos, o Nymphas Craterides, ite sub undas ; 

 Ite, recurvato variata corallia trunco 

 Vellite muscosis e rupibus, et mihi conchas 

 Ferte. Deae pelagi, et pingui conchylia succo." 



N. Parthenii Giannettasii Eel. 1, 



No. 1. JANUARY 1848, 



I. — On the Recent British species of the genus Lagena. 

 By W. C. Williamson, Esq. 



[With two Plates.] 



Whilst I was engaged upon a memoir on the microscopic 

 character of the Levant mud and other recent an'd ancient ocea- 

 nic deposits (printed for the forthcoming volume of the Me- 

 moirs of the Manchester Literary and Philosophical Society), 

 my friend W. Reckitt, Esq. of Boston placed in my hands 

 some sand obtained on excavating a well near that place, which 

 I soon found to abound in specimens oiLagen^^. Subsequently 



* This interesting deposit can scarcely be called recent, being probably 

 several thousand years old, and yet its geological character is not such as 

 to justify its organisms being introduced into the category of fossils; being 

 merely a beach which has been left permanently dry by the tide. When I 

 wrote the memoir above referred to, I stated " that a considerable portion of 

 the Fen district was once an estuary, which has undergone considerable 

 changes even since the time of the Roman invasion ; the old sea-bank 

 having, at that comparatively recent period, been much further inland than 

 at present " (iVTemoirs of the Manchester Literary and Philosophical Society, 

 vol. viii. p. 56). This estuary has been gradually filled up, the elevation of 

 the coast or the recession of the ocean causing the sandy debris, once form- 

 ing the bed of the latter, to be converted into dry land, and afterwards co- 

 vered over with a layer of vegetable mould. Mr. Reckitt's specimen was 

 obtained from a depth of seven feet below the surface, where he found a very 

 fine sand containing carbonaceous fragments, and a large number of the 

 Foraminifera and other microscopic organisms still characteristic of our 

 existing sea-beaches, including many of the rarest as well as the most 

 Ann. ^ Mag. N. Hist. Ser. 2. Vol.'i. 1 



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