60 FOSSIL TURTLES OF NORTH AMERICA. 
the rim of the orbit. Triturating surface of the maxilla furnisht with a prominent longitudinal 
ridge. Choanz opening on a line joining the fronts of the orbits. 
Key to Species oF BAENA. 
A". Judith River species. 
1. Length of anterior lobe 0.60, its width 0.82, of width of bridge; width of hinder lobe 
0.94 of width of bridge; entoplastron longer than broad ....................... callosa 
2. Plastron known only from part of anterior lobe; the entoplastron broader than long . . antiqua 
A*. Laramie species. 
1. Length of anterior lobe 0.92, its width 1.00, of width of bridge; width of hinder lobe 
1.04, Of width of brid gee. eens: aes rater ate eae hatchert 
2. Length of anterior lobe 0. 58, its length 0.79, of width of bridge; width hinder lobe 0.75 
of width oftbridpe’....s..s50c eae cence ee ee eee ee eee eee eerie marsht 
Av.) Torrejon species mo caa: coe care een ene Cee escavada 
A‘. Bridger species. 
1. Shell broad behind and deeply scallopt; strongly sculptured on back................ arenosa 
2. Not so strongly sculptured; a broad groove) alonp» the ibackvy «24-11 eres oie riparta 
3- Shell oval, thin; the sculpture broken up into wrinkles; no median groove .......... sima 
4. Shell oval; rounded behind; néanly,4smoothis- nt osc beee abe eee tel eee clara 
AP Unita speciestanciy: iy. Abteeity eR AE EA OT Ce Eee emilia 
Baéna callosa Hay. 
Plate 8, fig. 1; text-figs. 35, 36. 
Baéna callosa, Hay, Ann. Carnegie Museum, 11, 1904, p. 178, plate ix, text-figs. I, 2. 
This species is based on an incomplete shell which belongs to the Carnegie Museum, in 
Pittsburg, Pennsylvania. The number is 330. It was collected in the year 1903, by Mr. J. B. 
Hatcher, in the Judith River beds of Willow Creek, Gallatin County, Montana. 
The posterior fourth of the carapace is missing; and of the anterior three-fourths, many of 
the peripherals and portions of the costals are wanting (text-fig. 35). The entire length of the 
a) yoo. Son “ 
Figs. 35 and 36. Baéna callosa. Type. X#. 
35- Carapace. c.s. 1, c.s. 2, etc., costal scutes; v.s. 1, v.s. 2, etc., vertebral scutes. 
36. Plastron. ab, abdominal scute; am, anal scute; ent, entoplastron; epi, epiplastron; fem, femoral scute; g, gular 
; scute; hum, humeral scute; hyo, hyoplastron; hypo, hypoplastron; fg, intergular scute; mes, mesoplastron; 
pec, pectoral scute; xiph, xiphiplastron. 
