14 
Mr. W. C. Wiliiarnson on the Recent 
traces of a neck, which appears to wear away with age. Between 
this common form and that previously described, which I con- 
sider to be the perfect type, every modification exists. In some 
forms the costse terminate abruptly near the base of the neck, 
the superior portion being smooth. This condition obviously 
connects the L. striata with the var. /3. semistriata. In others 
the costae are continued longitudinally along the neck, whilst in 
a few elegant specimens in the cabinets of Messrs. Bean and 
JefiPreys they were wound spirally around it. In some examples 
I have noticed that the neck appeared to be atrophied and 
wasting, having lost its brittleness and become membranous, as 
if it were only of use in the early condition of the animal. The 
character of the decalcified membrane of this species has been 
already described (p. 8). 
Long. 
_l_ 
50 * 
1 
50 ' 
Diam. 
JL* 
60 
Long. 
1 
0 0 • 
Diam. 
•16 0 
100 
Reculver, Sheppey, Mr. Walker. Devonshire,^^ Montagu. 
Exmouth, — Clarke, Esq. Swansea, Rossilly, Manorbeer, Tenby, 
Oxwich, Caswell Bay, Sandwich, Oban, Kyleakin ; Roundstone, 
Connemara ; J\Ir. Jeffreys. Scarborough, Mr. Bean. Boston ; 
March. Fossil in a miocene tertiary deposit at Petersburg, U. S.f, 
Dr. Bailey ; also in the English crag, Mr. Searles Wood. 
L. striata, var. a. interrupta, nob. Eig. 7. 
Like L. striata, only the costse are more irregular ; sometimes 
they bifurcate, at others they are not continued over more than 
the half or two-thirds of the cell, no two being exactly the same 
length. The speeimen figured represents a common form of the 
neck when half-gone. 
Swansea, Rossilly, Manorbeer, Tenby, Oxwfich, Caswell Bay, 
Sandwich, Oban; Roundstone, Connemara; Kyleakin. Scar- 
borough, Mr. Bean. Boston ; March. Not uncommon. 
Lagena striata, var. semistriata, nob. PI. I. figs. 9, 10. 
Similar in most respects to some young states of L. striata, 
only the costse arising from the base terminate, some at the lower 
third, others at the middle, and in one specimen towards the 
uppermost third of the cell. What has been already said of the 
smooth neck found in some specimens of L. striata convinces me 
that this is only a variety. I have seen one specimen with a mucro 
at the base approaching the form of L. Icevis, var. Amphora. 
Long, yio ; 2h- 
* In this specimen nearly the whole of the neck is worn away. 
The same deposit lias also furnished examples ot' Eniosolenia globosa, ^re- 
thusa lactea, Flem., Renoidea ohlonga, Brown (both species Polymorphina. 
D’Orbigny), and what I believe to be young specimens of Rofalia Beccarii. 
