19 
British species of the genus Lagena. 
Cell ovato-globose, with a slight projection superiorly, at 
the extremity of which is the small circular oral ? orifice. Sur- 
face beautifully ornamented with numerous, small, white, concave, 
irregular, areolar spaces, separated by elevated, transparent, reti- 
cular lines of demarcation. These areolae are irregular in form 
and distribution, being sometimes nearly round or oval, but more 
usually exhibiting a marked tendency to become hexagonal, the 
lower ones being usually the most elongated. Occasionally the 
areolae are transparent and the reticulations milky. In this state 
it appears to be the L. reticulata of MacGillivray : one part of his 
description alone does not agree with my specimens ; he speaks 
of its being considerably compressed.^^ This however may have 
been an accidental circumstance, as all the species, both of En~ 
tosolenia and Lagena, are liable to a considerable degree of de- 
formity. Internal tube patulous, usually shorter than in E, 
globosa, and generally with a small dilatation or spherical cavity 
a little below the oral ? orifice. The base of the cell is sometimes, 
though rarely, furnished with a small umbo. 
In the figure of this exceedingly variable species, given in the 
Supplement to Montagues ^ Testacea Britannica,^ the areolae are 
made to represent scales overlapping each other. This appear- 
ance, though not natural, is easily obtained, by viewing the object 
obliquely and by throwing the microscope a little out of focus, 
and I have no doubt would be the aspect presented by the object 
when viewed under the imperfect instruments used in the time 
of Mr. Walker. Dr. Fleming considers these areolae to be pa- 
rietal cells.^^ They are however merely concavities in the exterior 
of the cell. They are usually to be traced in the form of opake 
spots in the decalcified membrane. 
I possess one curious abnormal double specimen of this species, 
like that of E, glohosa already described. There are two cells, 
united inferiorly, and having each one central oral ? orifice at the 
opposite extremity. 
Long. 
Diam. 
1 
1 
100 • • ' 
■ • Ts'S' 
1 
1 
TTJ • • ■ 
‘ • 15 0 
1 
1 G G • * ' 
’ • Too 
Seasalter, Mr. Boys,^^ Montagu. Torbay, Swansea, Mr. Jef- 
freys. Lamlash Bay, Ayrshire, Scarborough, Mr. Bean. Bay 
of Aberdeen,^-’ Prof. MacGillivray. Boston ; March : rare. 
Entosolenia squamosa, var. a. catenulata. PI. II. fig. 20. 
Lagenula catenulata, Jeffreys MSS. 
Cell ovato-globose, usually hyaline and transparent ; areolae 
very small and numerous, square or hexagonal, arranged in per- 
pendicular rows, having parallel horizontal divisions, which are 
2 * 
