JIOOEE ABNORilAL SECONDARY DEPOSITS. 545 



26. Fusus Jexyxsii, spec. nov. PI. XIY. figs. 6, 7. 



Shell elongate, fusiform ; whorls 7-8, angulated, bounded on the 

 lower margin by an elevated obtusely nodulated carina ; angulated 

 surface of the whorls covered by very close encii^ling striae, which 

 are decussated by equally faint lines, giving the shell, by aid of the 

 lens, a finely reticulated aspect ; columella moderately extended, lip 

 thick^ and at the base rather folded over the canal ; mouth rather 

 small, ovate. 



This shell is one of the commonest Gasteropods at Brocastle, 

 whence I have examples of all ages. It does not appear to have 

 attained any considerable size, my largest specimen being about half 

 an inch in length. It is named after the Rev. Leonard Jenyns, 

 F.G.S., the President of the Bath jSTaturalists' Club, and an earnest 

 worker in natural science. 



27. Helix Dawsoxi, spec. nov. PL XY. figs. 1, 2. 



SheU small ; spire but slightly elevated, with about four appa- 

 rently small convex volutions divided by a slight sulcus. 



The base of the shell is sHghtly crushed, but it is seen to be flat- 

 tened and to possess a deep and rounded umbilicus with a rounded 

 aperture. The somewhat imperfect condition of this shell, of v/hich 

 I have but one specimen, renders it rather difficult to determine 

 it with precision ; but its generic determination is facilitated by its 

 being found in association in the same deposit with the land and 

 freshwater genera I have previously enumerated. 



It is from the Charter-House Liassic lead-mine, and is named after 

 Dr. Dawson, the discoverer of a still older land-shell in the Coal- 

 measures of Nova Scotia. 



28. Hydeobia, sp. 



This genus is represented in the Charter-House Liassic mine, by a 

 single somewhat imperfect specimen, to which, being of young age, 

 I have not considered it desirable to give a specific determination, a 

 course the less to be regretted from my possessing examples from the 

 mines of other districts, which will be noticed on another occasion. 



29. LiTTORixA ovALis, spcc. nov. PL XIY. figs. 17, 18. 



SheU thick, ovate, convex ; spire rather short ; volutions 4-5, 

 the body-whorl being convex, longitudinally ovate, and inflated. 

 The body-whorl has numerous regular, obtuse, encircKng striae, 

 which continue on the base, but which are less distinct on the 

 upper whorls ; these are decussated by close, rather curved, longi- 

 tudinal striae. 



Loc. The coralliferous conglomerate of Brocastle, whence I have 

 obtained two specimens. 



30. LiTTORixA ciRCULAEis, spcc. nov. PI. XIY. figs. 15, 16. 



SheU smaU, turbinated ; spire acuminated ; volutions 4-5, convex, 

 and divided by the suture ; whorls ornamented by regular encircling 

 striae, about nine in number on the last whorl, which are followed 



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