22 GEOLOGY. 



Lavelley, — . Tunnel sous-marin entre la France efc I'Angleterre. 



(Seeing. Civ. Paris.) Moniteur Imlustriel Beige, Feb. 10 and 21, 



pp. 74-76, 90, 91. 



A general description of the proposed tunnel, noting the characters 



of the rocks on the coasts, and giving an account of recent submarine 



surveys to determine the outcrop of the Chalk across the Channel. 



W. T. 



Lavis, H. J. J. On the Triassic Strata which are exposed in the 



Cliff-sections near Sidmouth, and a Note on the occurrence of 



an Ossiferous Zone containing Eones of a Lahyriyitliodont. 



Quart. Journ. Geol. Soc, vol. xxxii. pp. 274-277; 2 woodcut 



sections. 



The cliffs are capped by Chalk and IT. Grecnsand, beneath which 



comes the Triassic marl overlying sandstone. The " ossiferous zone " 



occurs near the top of the sandstone. Details of the cliff-section are 



given. W. T. 



Notes on the Geology of Lewisham. Proc. Geol. Assoc. 



vol. iv. no. 9, pp. 528-543. 

 The beds described range from U. Chiilk to London Clay. 

 Comparative sections are given of the Lower Tertiaries of Charlton 

 and Lewisham ; also diagrams illustrating the corresponding condi- 

 tions of deposit in the two districts. A list of minerals is ap- 

 pended. W. T. 



Lebour, G. A. On the Larger Divisions of the Carboniferous 

 System in Northumberland. Trans. N. Engl. Inst. Eng. vol. xxv. 

 pp. 225-237, pi. 70. 

 The object is to propose certain changes in nomenclature. The 

 definite boundaries adopted from the S. of England are objected to, 

 especially in the case of the Millstone Grit, Gannister Beds, and 

 Coal Measures. These are regarded merely as subdivisions of the 

 JJ. Carboniferous Group. Taking the highest bed of limestone (Ecll- 

 Top Limestone) as the upper limit, all below are assigned to the L. 

 Carboniferous Group — the upper part embracing the Yoredale rocks, 

 the middle part the divisions of the Limestone Series as proposed by 

 Phillips and G. Tate, the lower part the Tuedian or Calciferous Sand- 

 stone Series. The author recognizes no clear lines between the divi- 

 sions of his lower group. The Tuedians are for the most part different 

 in character from the beds above them ; but it is contended that the 

 upper beds of this scries dovetail into, the lower beds of the division 

 next above, so that no definite line can be drawn through the county. 

 The beds between the Fell-Top Limestone and the Tuedians are called 

 the Bernician Series, the term Yoredale being abandoned (see Geo- 

 logical Eecohi) for 1875, p. 28). The author proposes his divisions 

 for Northumberland only, remarking that classifications of the Car- 

 boniferous rocks can have only a local value. W. T. 



