PLATURUS LATICAUDATUS. 



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dorsal region than the rings, and broader upon the abdomen. Head 

 black, except the fron to-rostral region, which is yellow. Middle 

 region of throat yellow also. 



SYN. Coluber laticaudatus, LINN. Mus. Adolph. Fred. 1754, Tab. xvi, fig. 1. 

 THUNB. Acad. Ups. 1787, 11. 



Hydrus fasciatus, SCHN. Hist. Amph. I, 1799, 240. 



Platurus fasciatus, BAUD. Hist. nat. Kept. VII, 1803, 226, PI. LXXXV. MERR. 

 Tent. Syst. Amph. 1820, 142. DUM. & BIBR. Erpet. gen. VII, n, 1854, 1321. 



Plulurus latican.da.tm, WAGL. Nat. Syst. Amph. 1830, 166. 



OBSERV. The synonyms not included either under this or the fol- 

 lowing species were intentionally left aside, preferring an omission to 

 an erroneous quotation. 



DESCR. The head is depressed, and but slightly broader than the 

 neck. The snout is blunt, rounded, and nearly even with the extre- 

 mity of the lower jaw. The vertex plate is subcordiform, broad, and 

 rounded anteriorly, pointed posteriorly. The occipitals, which are 

 well developed, are subtrapezoid, slightly rounded exteriorly, and 

 larger than the vertex plate itself. The supraoculars are short, and 

 irregularly rounded. The postfrontals are but very little larger than 

 the prefrontals, which are subtriangular. The nasal plate is elongated 

 and single, resting upon the first and second labials, and limited above 

 by the prefrontal; sometimes, also, reaching the edge of both the third 

 labial and poatfrontal : the nostril is situated posteriorly to the middle 

 of its length. A high and subquadrangular anteorbital may be observed 

 situated rather obliquely upon the third labial, limited superiorly by 

 the supraocular and the postfrontal. The eye, the pupil of which is 

 round, is not very large, and circular in shape. There are two well-de- 

 veloped subangular postorbitals; the lower one somewhat larger than 

 the upper, and situated above the commissure between the fourth and 

 fifth labials. The temporal shields, five or six in number, are a little 

 larger than the scales about the neck. The rostral plate is subpyra- 

 midal, with its summit contiguous to the prefrontals, thus isolating en- 

 tirely the nasals. There are seven upper labials; the third and fourth 

 are the largest, and constitute the inferior rim of the orbit ; the fourth 

 entering altogether into it, and the third only in part. The symphy- 

 seal is exceedingly small, with two small labials on either side ; the 

 remaining labials constitute two rows : an upper, in which they are 



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