24 THE FOBAMINIFERA 



MiLiOLiNA TRiCARiNATA. — This shell, triangular in section, 

 has plane sides somewhat resembling a plump beech-nut kernel. 

 It occurs but sparingly. 



MiLiOLiNA AuBERiANA is triangular, somewhat like the last 

 species, but one of the sides is shorter than the others, of which 

 one is pierced by the acute edge of an earlier segment. 



MiLioLiNA OBLONGA. — This is an elongated form, closely 

 allied to M. seminulum^ and is frequent. 



MiLiOLiNA SEMiNULUM. — One of our commonest species, a 

 highly-polished, broadly oval form, with rounded edges ; frequent. 



MiLiOLiNA SECANS. — Our largest British MiUolina is very flat 

 and thin, with sharp edges, broadly oval to round. It is fre- 

 quently marked by transverse, curved wave-lines of growth ; 

 common. 



MiLioLiNA SUBROTUNDA. — In some gatherings, the predomi- 

 nant form, with roundish segment, often broader than long, the 

 inner margin of every segment forms an adhering rim to the seg- 

 ment it clasps ; the surface often flattened, wavy, and irregular ; 

 common. A few specimens have rib-like markings on the peri- 

 pheral margin. 



MiLiOLiNA BicoRNis has longitudinal striae, and a more or less 

 flattened mouth. There is a tendency for the inner segments to 

 be heaped up in the middle of one surface, while they are 

 scarcely seen on the other and flatter side ; rare. 



MiLiOLiNA Brongniartii, a variety of M. bicorfiis, with a 

 rounder and protruded aperture ; very rare. 



MiLiOLiNA FUSCA, a Small, oblong, brown, arenaceous Milio- 

 lina ; though " rare," yet, by comparison with its rarity elsewhere, 

 it is frequent. 



MiLiOLiNA SCLEROTICA. — This rough, angular Miliolina has an 

 appearance approaching to arenaceous ; there is a similar shell, 

 with round, inflated chambers; may be but a variety oi M. seminu- 

 liim ; frequent. We should say neither was truly arenaceous. 

 Many of the specimens closely resemble the Qidnqiieloculina con- 

 torta of D'Orbigny in form, but his species, as described by him, 

 is smooth. 



Spiroloculina planulata — a few small specimens. Here 

 we have long, narrow chambers, arranged biserially, in one plane, 

 forming a broad ellipse, chambers opening alternately at each end. 

 The specimens are hardly developed enough to decide whether 

 they belong to the group, "■ Planulata" or '' Limbata^' but the 

 limbate sutures not being apparent, it seems safe to class them 

 with the former. 



