TESTUDINATA. 
53 
the latter, the outer border of the hinder lobe formed a high wall, 
perpendicular on its outer face. Between the furrow separating 
the abdominal and the femoral scutes and the hypo-xiphiplastral 
suture the height of the wall is 90 mm. The summit of the wall is 
narrower than in Leidy’s species. The outline figures (figs. 4, 5, 
pi. 9) represent sections taken at the hypo-xiphiplastral suture 
of the two species at the place described. It will be seen that in 
T. crassiscutata (fig. 4) the bone is everywhere thicker. Toward 
the midline of the lobe, 90 mm. from the outer border, the thick¬ 
ness in Leidy’s species is 36 mm.; in the one here described, only 
26 mm. 
The furrow between the abdominal and femoral scutes de¬ 
scends from the summits of the wall mentioned to the lower sur¬ 
face of the bone. After passing inward and forward about 40 mm. 
it turns and passes inward and backward, making an angle of 
about 6o° with the outer border. On the lower surface of the bone 
it is a very broad, illy defined groove. 
BYSTRA, NEW GENUS. 
Diagnosis. —Like Testudo, but small and with heavy shell, an¬ 
terior end of plastron not emarginate at the ends of the gulo-hu- 
meral sulci. These sulci running nearly straight across the plas¬ 
tron and lying wholly in front of the entoplastron. Supercaudal 
scute single. Type Bystra nanus. Named in honor of the discov¬ 
erer of the type specimen. 
BYSTRA NANUS, NEW SPECIES. 
Plate I. 
Type-specimen. —A complete and only slightly injured shell be¬ 
longing to Dr. Henry G. Bystra, of Brooksville, Fla. 
Type-locality and formation .— Holder, Florida. Found in a 
phosphate mine and belonging probably to the Miocene or Plio¬ 
cene. 
Diagnosis .— Besides the characters given under the definition, 
the plastron of the type has a truncated and much thickened beak; 
. a rather deeply notched hinder lobe, which is thick in front; and 
vertebral scutes of moderate width. 
This specimen (pi. I) was found in the operations of mining 
for phosphate rock. It was enclosed in a mass of silicious sand, 
most of which was cemented into a hard mass. The left side of 
