41 



that the two species are identical. On account of the poorness of the type specimens of 

 C. ogmius and to avoid confiision the specific name variolosus is retained. 



Fio. 6. — Anterior half of the shell of Adocus variolosun, from Red Deer river ; ventral aspect showing the front margin 



of the carapace, One-fifth natural size. 



The foregoing characters indicate a Chelonian that cannot be retained in the genus 

 Compsemys, which is closely allied to Pleurosternon and possesses a mesoplastral element. 

 The presence of two small gular shields separated by a divided* or double intergular 

 shield (in reality two intergulars), and of a series ot inframarginals, the absence of a 

 mesoplastral and of a sutural union of the pelvis with the plastron, together with an 

 abbreviation of the lobes and a decided lengthening of the sternal bridge are characters 

 that suggest such close affinities to the genus Adocus of Cope, that this species has been 

 referred to that genus. 



Measurements. 



M. 



Estimated length of plastron (281 inches) ■ 720 



Length along median line from anterior end to posterior border of pectoral 



shield -295 



Breadth from median line to lateral suture (= half of breadth of plastron)., "280 



Length of entoplastral • 085 



Maximum breadth of entoplastral -123 



Thickness midway between gulars • 035 



Thickness at centre of gular shields -033 



Thickness on median line at posterior border of pectoral shield '013 



Thickness at posterior edge of hyoplastral near left boundary of abdominal shield ■ 007 



Thickness in axillary region near lateral suture '032 



Thickness mid way between entoplastral and the axillary notch. ■ 025 



'G. Baur. Proc. Acad. Nat. Sci. Philadel, vol. xliii, 1891, p. 428. The genus Adocus. 



6 



