202 O. Dowker — Water-supply of East Kent. 



disjoined from the penultimate posteriorly at the aperture ; columella 

 very short, and twisted horizontally, terminating in a prominent 

 bluntly-pointed tooth, in front of which is a narrow groove. The 

 shell is smooth and shining, but under a strong lens its whole surface 

 up to the basal ridge above referred to is seen to be covered with 

 numerous fine encircling striae, and still finer curved radial strige. 



Dimensions. — Height, 4 millimetres ; diameters, 5 mm. and 

 5-75 mm. 



Geological Position and Locality. — Upper Lias, zone of Am. ser- 

 pentinus, Lincoln. 



EXPLANATION OF PLATE V. 

 Fig. 1, a, b, c. Trochus Dalbiensis, sp.n. — Lower Lias, zone of Am. oxynotus, Old 



Dalby. Back and front views and base enlarged 



twice, penultimate whorl enlarged six times. 

 ,, 2, a, b, c. Trochus Thetis, Miin. — Lower Lias, zone oi Am. oxynotvs, Old Dalbj'. 



Back and front views and base enlarged twice, 



penultimate whorl enlarged six times. 

 ,, 3, a, b. Trochus CricJci, sp.n. — Middle Lias, zone of Am. margaritaius, 



Daventry. Back and front views enlarged three 



times, penultimate whorl enlarged six times. 

 „ 4, a. Trochus sayenatus, sp. n. — Upper Lias, Watford. Back and front 



views, enlarged three times. 

 I) 5, a. Trochus Northamptonensis, sp.n. — Upper Lias, zone of .^wi. commMMis, 



Weedon. Back and front views enlarged twice. 

 ,, 6, a, b. Trochus Niortensis, d'Orb. — Middle Lias, zone of Am spinatus, Down 



Cliff. Front and basal views enlarged three times, 



penultimate whorl enlarged six times. 

 )) 7, a. Amherleya Callipyge. sp. n. — Middle Lias, zone of Am. margaritatus, 



Daventry. Front and back views enlarged three 



times. 

 ,, 8, a, b. Ifonodonta humilis, sp. n, — Lower Lias, zone of Am,, oxynotui. Old 



Dalby. Front, back, and apical views enlarged 



four times. 

 ,, 9, a, b. Ifonodonta Lindecolina, sp. n. — Upper Lias, zone of Am. serpentinus, 



Lincoln. Back and front views enlarged twice, 



portion of penultimate whorl enlarged six times. 

 ,, 10, a. Cerithium trigejnmatum,. sp n. — Lower Lias, zone of Am. oxynotus. 



Old Dalby. Back and front views enlarged six times. 

 ,, 11, a. Actmonina ferrea, sp. n. — Middle Lias, zone of Am. spinatus, Tilton, 



Back and front views enlarged three times. 

 11 12, a. Cylindrites cequalis, sp. n. — Middle Lias, zone of Am. .spinatus, Tilton, 



Front and back views enlarged twice. 

 » 13. Alaria Hudlestoni, sp. n. — Lower Lias, zone of Am. Bucklandi, Bitton. 



Front view enlarged three times. 

 ,< 14. Alaria semicostulata ? Piet et Eug. Desl. — Upper Lias, zone of Am. 



serpentinus, Dodford. Back view enlarged twice. 

 t) 15. ,, ,, ? — Upper Lias, Chipping Warden. Front view 



enlarged twice. 

 {To be continued.) 



IT- — The Watek-Supply op East Kent, in Connection with 



Natural Springs and Deep Wells. 



(Being the substance of a Paper read before the East Kent Natural History Society.) 



By George Dowker, F.G.S. 



THE numerous demands made upon our underground water-supply, 

 both for sewage and sanitary as well as brewing purposes, 

 render the subject of my paper a matter of deep and serious im- 

 portance. 



I shall set forth in the first place the rise and course of the rivers, 



