i6 
S. s. BUCKMAN, 
(Schwed. Südpolar-Exp. 
Bouchardia ovalis, sp. n. 
Plate I, fig. I. 
Remarks: This form is broader than the others and has a relatively short 
beak-area. 
P'rom B. tapirina, HuTTON, this form differs in being less circular and in having 
a larger beak-area; from B. rhizoida, HuTTON, in being more regularly elliptical. 
From both of these large New Zealand species this form differs in having the an- 
terior sinuation. 
Locality: Seymour Island (ii), off Graham Land, Antarctica. 
Formatio)i: Seymour Island younger beds. 
Material: Two specimens which are worn: they look as if they might have 
been derived from an older rock, but examples of other forms are in somewhat 
similar condition, due perhaps to atmospheric agencies. 
Bouchardia antarctica, sp. n. 
Plate I, figs 2, 3. 
Remarks: The strong carination of the ventral valve is a feature of this form. 
It is narrower than B. ovalis^ and in the adult the straight sides are a distinctive 
feature. In the young examples the shape is more like that of B. ovalis, but it 
tapers more anteriorly, the carination is stronger, while the dorsal valve is flatter, 
showing slight median sulcation. 
Locality: Seymour Island (il), off Graham Land, Antarctica. 
Formation: Seymour Island younger beds. 
JSLatcrial: Twenty specimens, mostly in good preservation. 
Bouchardia angusta, sp. n. 
Plate I, fig. 4; Plate III, fig. 2. 
Remarks: This form might be described as a dwarf development of B. antarc- 
tica; for at a small size it has much the shape of the adult of that species. Instead, 
however, of having sides which are nearly parallel for some distance, it tapers an- 
teriorly from the hinge-line, which is then the widest part. It further differs from 
B. antarctica in not having the distinct carination of the ventral valve; also in 
having a straighter hinge-line. 
Locality: Seymour Island (ii), off Graham Land, Antarctica. 
Formation: Seymour Island younger beds. 
Material: Four specimens. 
