314 



PROCEEDINGS OF THE \ l'//n\ \i. MUSEUM. 



vol. 38. 



verse section taken at the widest part of the fragment, which is 

 apparently not far in front of the outer ends of the humero-pectoral 

 sulci; fig. S presents a perpendicular section along the midline. 

 The greatest thickness of the lip is 55 mm. Its width at the gulo- 

 intergular sulci is 100 mm.; at the gulo-humeral sulci it must have 

 been at least 120 mm. The lip of B. sinuosa is only 95 mm. wide at 

 the latter-named sulci. 



It is in the conformation of the intergular and gular scutes that are 

 found the characters that most clearly distinguish this species from 

 the two others mentioned. In B. variolosa the intergulars are very 

 large and extend backward to or on the entoplastron; while the gulars 

 are small and are crowded far away from the midline. In B. sinuosa 



Pigs. 6, 7.— Basilemys prjeclara. x£. 6, lower surface of front end of plastron; ml, ento- 

 plastron; epi, epiplastron; yul, gular scute; intg, intergular scute; 7, SECTION across front 



END oK PLASTRON A LITTLE IN FRONT OF ENTOPLASTRON. 



the intergulars are much like those of B. variolosa, but the gulars 

 extend inward and join each other on the entoplastron. In B. prse- 

 clara the intergulars lack much of reaching backward to the ento- 

 plastron, while the gulars meet each other on the epiplastra and the 

 entoplastron. The anterior end of the sulcus between the gulars 

 is about 66 mm. behind the front of the lip; the hinder end about 

 12 I nun. behind the front. 



A fragmenl of the rim of the plastron belongs behind the left ingui- 

 nal notch and includes the suture between the left hypoplustron and 

 the left xiphiplastron. The thickness of the bone at the suture is 

 17 nun. Fig. 9 shows a section taken 40 mm. behind this suture. 

 The outer sculptured surface of the bones rises nearly perpendicu- 

 larly from the Hat lower surface to the summit of the ridge that 



