PLATE LXXIX. 
Concavum-zone. 
Figs. 1—6.—Sonninia crassiFormis, S. Buckman. 
Fig. 1.—Side view of an immature example, showing the regularity of the 
large spines. Bradford Abbas. My Collection. (Page 348.) 
Fig. 2.—Outline of the whorl-section. 
Fig. 3.—Side view of the type—a large adult example—reduced to about one- 
third of the natural size, the specimen bemg 290 mm. against 95 mm., the 
diameter of the figure. (The umbilicus is 124 mm. across.) Bradford Abbas. 
My Collection. 
Fig. 4.—View of the other side of the same fossil similarly reduced. (These 
two figures are copies from photographs, and they illustrate the difference made 
by presence and absence of test.) In fig. 3 the ribs of about the first half of the 
outer whorl have the test preserved, but it is absent from the last portion, and 
the small size of the last three ribs, with appearance of constriction of the whorl, 
is noticeable. (At the bottom of the whorl in fig. 3 the ribs are not shown 
strongly enough.) In fig. 4 the ribs of the outer whorl are without test (the first 
part is somewhat damaged); but the test is present on the last two ribs as well 
as on the part of the mouth-border which this figure illustrates. The thickness 
of the test may be judged from the size of the penultimate rib and the 
somewhat inflated appearance of the mouth-border,—in fact, in places the test 
is 5 mm. thick. The body-chamber of this specimen is very short—less than 
half a whorl. 
Fig. 5.—Outline of the whorl-section—one side somewhat restored. Natural 
size. i 
Fig. 6.—Suture-line of the same specimen, showing a tetradactyloid superior 
lateral lobe. 
Figs. 7, 8.—Sonninia, sp. 
Fig. 7.—Side view of a small shell. Bradford Abbas. My Collection. 
(Page 349.) 
Fig. 8.—Front view of the same specimen. 
