BOTHREMYDID^. 



117 



the peripheral with the obtuse canna is the more anterior, the one with the acute carina 

 belonging near the inguinal notch. 



Portions of the right and left first costals are present. These fragments show that these 

 bones had an antero-posterior width of about no mm. The thickness at the neural border is 

 between 9 mm. and 10 mm. On the inferior side of the bone is seen the base of the rib-head; 

 in front of this a sharp ridge corresponding to the first rib. Each of the first costals articulated 

 with four peripherals. A ridge proceeding from the rib-head becomes, toward the peripheral 

 border, high and broad. In this is excavated a large pit, 20 mm. wide and rising about 50 mm. 



b 



113. 114. 115. 



FIGS. 113-115. Taphrosphys mo/ops. Xj. Xo. 1472 A. M. N. H. 



113. Sections of a bridge peripheral, a, anterior end; b, posterior end. 



114. Sections of another peripheral of bridge, c, anterior end; d, posterior end. 



115. First costal, inner surface. Shows axillary pit. 



above the lower border of the costal (fig. 115). This is for the reception ot the axillary buttress. 

 Its upper end is much the deeper. 



There are fragments of the second, third, fourth, fifth, and sixth costals. These are 

 represented in the restoration (fig. 112). From the proximal end of costals three and four we 

 get an idea of the forms of neurals, but only approximate information regarding their widths. 

 The third costal is 12 mm. thick at the neural border but only 6 mm. at the distal end. The 

 fifth and the sixth costals are wider than those preceding them, as in T. longinuchus. 



FIG. 116. Taphrosphys molops. Anterior half of plastron of type. 

 Known portions stippled, m.p, mesoplastron. 



xj. 



The upper surface of the nuchal and the anterior peripherals is rather strongly sculptured 

 with a network of grooves. The interspaces vary greatly in form and size, few being less than 

 5 mm. in diameter. Of the bridge peripherals one face is distinctly sculptured, the other 

 obsoletely so. The sculpture on the costals is distinct, but usually not so strongly exprest as on 

 the nuchal. The deepest furrows are mostly nearly parallel with the long axis of the costal. 



The sulci are shallow but distinct. There is no nuchal scute. The sulcus between the 

 first marginals is 58 mm. long. Each measures 66 mm. along the free border. The second 

 marginals had an equal extent along the free border. The width at the anterior end is 60 mm.; 

 at the distal end, 40 mm. 



