180 



of the frontals (n), by the junction of the prefrontals (14) and postfrontals (12) above the 

 orbits : the prefrontals are bent down more abruptly to the external nostril ; the mastoids 

 unite with a larger proportion of the parietals. It differs from the Loggerhead (Chelone 

 caretta), by the greater breadth as well as the greater curvature of the prefrontals, and by 

 the greater length of the parietals. The excavation beneath the basioccipital and basisphe- 

 noid is less deep than in Chelone mydas. The tympanic excavation of the mastoid is less 

 deep than in Chelone caretta. 



Hunterian. 



911. The skull of a Hawk's-bill Turtle (Chelone imbricata, Schweigger *), in longi- 



tudinal section, and partially disarticulated. 



It resembles the Chelone mydag in the extension of the frontal to the superorbital border, 

 but a larger proportion of the squamosal articulates with the postfrontal. The tympanic 

 excavation of the mastoid is deeper, and the digastric excavation of the same bone is wider 

 and shallower. The numbers on the bones indicate their names according to the Table of 

 SYNONYMS. 



Hunterian. 



912. The skull of a large Loggerhead Turtle (Testudo caretta, Linn.; Testudo marina 



Caouanna, Ray ; La caouane, Guv.; Chelone Caouana, Schweigger). The num- 

 bers indicate the names of the individual bones according to the Table of 

 SYNONYMS. 



The extreme length of this skull is 13^ inches ; the extreme breadth, 10j inches. 



Purchased. 



913. The skull of a large Loggerhead Turtle (Chelone Caouana), with the spine of 



the superoccipital broken away, and the horny covering remaining on the upper 

 mandible. 



The extreme length of this skull ia 14| inches; the extreme breadth, lOf inches. The 

 entire animal weighed upwards of 1600 pounds. 



Mus. Leverianum. 



914. The skull of the Loggerhead Turtle (Chelone Caouana). It is a little mutilated 



behind : the horny covering of the mandibular part of the lower jaw is pre- 

 served. Hunterian. 



* Not the same species as that termed ' Chelonee Caret,' of which the skull is figured by Cuvier, in 

 the 'Ossemens Fossileo,' 4to, torn. v. part 2. pi. 11. figs. 1-4. 



