318 Mr. F. Chapman on 
Lower and Middle Magnesian Limestone of the North of 
England. 
The specimens of A. milioloides from Wedmore are more 
compressed than those obtained from Permian deposits, but 
they agree in the general plan of growth. The Rhetic 
specimens are alee much smaller than those of Permian age, 
micas Unie only 35 inch (0°56 millim.) in length, whilst the 
latter are >> ‘nah (1: 75 millim.). 
A. milioloides occurs in the Kheetic clay, bed no. 2, at 
Wedmore, and is common. 
11. Ammodiscus pusillus (Geinitz). 
(Pl. XI. fig. 14.) 
Serpula pusilla, Geinitz, 1848, Verstein. Zechst. Roth. p. 6, pl. iil. 
figs. 3- 
Foraminites serpuloides, King, 1848, Cat. Perm. Foss. Northumb. 
Ser mila® pusilla, Jones, 1850, in King’s Monogr. Perm. Fossils, p. 57, 
pl. vi. figs. 7-9, pl. xviii. figs. a—d. 
Trochammina pusilla, Jones, Parker, and Kirkby, 1869, Ann. & Mag. 
Nat. Hist. ser. 4, vol iv. p. 390, pl. xiii. figs. 4— 6 bes ; Brady, 1876, 
Monogr. Salk and Perm. Foram, (Pal. Soe.) p. 7 8, pl. iil. figs. 4,5; 
Heeusler, 1882, Ann. & Mag. Nat. Hist. ser. 5, vol: xen pe 58, pl. iv. 
figs. 27-30; LG. Bornemann, 1885, Jahrb. k. preuss. geol. Landes- 
anst., Berlin, p. 293, pl. xiii. figs. 6, 7. 
Ammodiscus pusillus, Heusler, 1890, Abhandl. Schweiz. paleontogr. 
Gesellsch. vol. xvii. p. 60, pl. ix. figs. 89-43, 
The Rhetic examples of the above species are both rare 
and very small; the test is finely arenaceous, as is the case 
with most of the specimens from the black Rheetic clay. 
A, pusillus is acommon form in the Permian (lower and 
middle Magnesian Limestone) of the north of Kngland (asso- 
ciated with A. milioloides) ; it is also recorded from the 
Zechstein of Germany; also from Triassic rocks in Thu- 
ringia by L. G. Bornemann; and from the Upper Jurassic 
beds of Switzerland by Heeusler. 
Found rarely in bed no. 2 of the Rheetic series at Wedmore. 
12. Ammodiscus Robertsoni (Brady). 
(Pl. XI. figs, er die) 
Trochammina Robertsoni, Brady, 1876, Monogr. Carb. and Perm, 
Foram. (Pal. Soc.) p. 80, pl. iii. figs. 6, 7. 
One of the commoner forms in the washings of the black 
Rhetic clay of Wedmore is the elegant little species of 
Ammodiscus which Dr. Brady found in the Carboniferous 
shales of the west of Scotland. The finely arenaceous texture 
of the test of the Rheetic specimens exactly accords with the 
