W. H. Hudleston — Recent Wells in Boraet. 243 



There are no grounds for generic definition at present, but the genus 

 is probably undescribed. And in the absence of evidence of other 

 generic characters than the dense folding of the tooth substance it may 

 be sufficient to record the species as Sijphonodon thecomastodon. 



The photographs were made for me by A. Campion, Esq., in the 

 Metallurgical Laboratory, Coopers Hill. The transverse section is 

 enlarged four diameters and the segment is enlarged twelve diameters. 



EXPLANATION OF PLATE X. 



Fig. 1. — Transverse section of the summit of the crown of the tooth of the 



Labyrinthodont reptile Sijphonodon, rather more than four times the natural 



size ; broken on the margin in polishing. 

 Fig. 2. — A segment of a transverse section of the same tooth, about twelve times 



natural size, showing a few of the radiating plates of folded tubes of dentine. 



Externally a few of the close-set quadrate tubes are seen whiah form the sheath 



to the tooth and suggest the triA-ial name thecomastodon. 



II. — On some Eecent "Wells tis Doesei. 



(Pakx II.) 



By W. H. Hudleston, M.A., F.E.S., F.G.S. 



{Concluded from the May Number, p. 220.) 



II. The Bovington" Boeehole. 



FOR some years past the troops encamped at Bovington had to be 

 content with such water as was supplied by a well a few hundred 

 yards to the S.S.E. of the recently excavated borehole. The following 

 particulars have been gathered respecting this well, but I cannot 

 guarantee that in all respects they are strictly accurate. It was sunk 

 in the Bagshot Beds about 1899, and is said to be 87 feet deep; the 

 water-level stands at 82 feet from the surface, and the yield is 

 360 gallons per hour. The same Bagshot water-level was struck in 

 the borehole. On comparing these two water-levels it is found that 

 the one in the borehole stands at 85 feet above Ordnance Datum, 

 whilst that in the well stands at 73 feet above O.D. This difference 

 of 12 feet in a horizontal distance of 450 feet amounts to 1 in 37'5, 

 showing a dip in the Bagshot Beds of 1J° to the S.S.E. This may 

 not exactly represent the direction of maximum dip, but there are 

 good reasons for believing that the line of maximum dip of the 

 Bagshots hereabouts is not far from S.S.E. 



Since the "War Office was not satisfied with the amount of water 

 yielded by the well they bethought themselves of obtaining an artesian 

 supply, and accordingly entered into a contract for the execution of 

 a borehole, which was to be prosecuted to a depth of 600 feet, unless 

 a good supply of water was reached at a less depth. ^ Ultimately the 

 boring was continued to a depth of 726 feet, and the following is 

 a record of the beds encountered : — 



1 The engineers employed were Messrs. Le Grand & Sutcliff. The operations 

 lasted from July to November, 1906. 



