26 
VINE : CAMBEIDGE GEEENSAND. 
Mr. Jesson's collection, and every aspect of individual growth can 
be studied with perfect safety, but I am not prepared to enter into 
a full discussion of the minute structures given by Mr. Sollas. One 
remark, however, ma}^ be quoted from his paper. Speaking of the 
species of Webbina, described below, he says, " It did not occur to 
me to question the arenaceous character of (Webbi/ui), till in 
examining a thin slice of Yentriculite. ... I observed two 
specimens of a foraminifera in section presenting the same outline 
of that of the supposed W. irregularis, and adherent hke it to a 
piece of coprolite. . . . Both these sections exhibit in an 
unmistakable manner the tubulation of the shell-wall which dis- 
tinguishes the Vitrea perforata. . . . And next and most 
important, that these Webbinm are truly perforate foraminifera." 
Geol. Mag. loc. cit. pp. 102-103. 
21. — Webbina tubeeculata, Sollas, PL II., fig. 14. 
Sollas : Geol. Mag. 1877, p. 104, pi VL, figs. 4 to 7 and 9. 
Surface of test ornamented by a number of tubercles irregularly 
(?) disposed, generally hemispherical and depressed, resembling 
rivit- heads of an iron girder. 
Locality : Cambridge, Greensand. 
This is a very abundant form in Mr. Jesson's material, and 
I can fully endorse Mr. Sollas's remarks as to the peculiar 
ornamentation of the surface. Occasionally the ornamentation is so 
regular that it is possible to count the tubercles as they are disposed 
in rows. 
22.— Webbina l^vis, Sollas, PI. II., fig. 13. 
Sollas, Geol. Mag. (op. cit. p. 103-4.) pi. VI., figs. 1-3. 
? Trochammini (Webbina) irregularis Dr. Hausler, Ann. Mag. Nat. 
History. Ser. 5, Vol. 10, pp. 349-337, pi. XV., fig. 15. 
Surface of test smooth, not tuberculated. 
Locality : Cambridge, Greensand. 
In his remarks on the latter species Mr. Sollas says (loc. cit., 
p. 104), " As the contents of the Cambridge Greensand bed have 
been subjected to very considerable attrition, it is just barely 
possible that W. Icuvis^ is simply W. tuberculata with its outer 
tubercles worn off. The smooth, beautifully finished appearance of 
