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THE HATKACIIIA OF NORTH AMERICA. 



217 



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imlly to the extremity of the roninled muzzle. It is much depressed 

 iilso, so liiat ■ha ranfje of vision is verticsil. The end of the muzzle pro- 

 jects beyond the mouth, but the sides do not project. The number of 

 lateral dermal {jrooves is about sixty. 



The eyes are quite small, and are separated by an interspace of five 

 times their transverse diameter. They have no lids, so that the cornea 

 is continuous with the cephalic epidermis. The external nostrils are 

 minute, and are separated by an interval a little less than half the in- 

 terorbital space. The lips are larjje and full, th(Kse of the upper jaw 

 ()verhan<jinjj, and concealing those of the lower except at the end of the 

 muzzle. The lower lips commence on each side of the symphysis, and 

 are decurved over the integument of the ramus, from which they are 

 separated by a deep longitudinal groove. 



In the premaxillo -maxillary series there are thirty-one teeth. The 

 series terminates below a point posterior to the eye, and a little in front 

 of the rictus oris. The vomerine series form a /\ with the apex forwards. 

 Tiieir posterior end is nearly but not Jiuite so far jmsterior as the ex- 

 tremity of the maxillary row. All the teeth are comi)ressed, and their 

 anterior edge is abruptly recurved towards the apex, so that the apex 

 looks partly posterioily. The posterior nares have a valvular ojjening, 

 which looks ba<!k wards and outwards a little in advance of the ex- 

 tremity of the vomerine series, and nearer to them than to the maxil- 

 laries. The tongue is represented by a muscular mass, which occupies 

 the floor of the mouth. It is only free laterally, being separated by a 

 deep groove from the mandil)ular ramus. This groove is vertically 

 divided by a membranous lamina for its entire length. 



The skin is everywhere smooth. The segmental grooves are onlj' dis- 

 tinct on the sides; on the belly they are indistinct, and on the dorsal 

 region they are entirely wanting. There are numerous nuicous pores 

 on the head. There are three rows on the maxillary region, the superior 

 of which ceases below the eye, in front of a line falling perpendicularly 

 (Vom it. Tiie median row terminates in one or two large pores a little 

 behind below the eye. The inferior row extends farther and then be- 

 i'omes transverse, and joins (he superior branch of the sui>ercili; -y row 

 three diameters of the eye behind an<l within it. There is a row on each 

 side of (he muzzle, which terminates in front of a line co;inecting the 

 fronts of the eyes. Its place is taken by a superciliary row, which forks 

 behind (he eye. The inferior half ceases behind the eye two diameters, 

 while thei superior one joins the transverse continuation from theinf(!rior 

 maxillary, and is continued a short distance over each temporal muscle. 

 There are no distinct rows of pores on the body. The head pores may 

 dilfer somewhat from those described above from a large specimen 

 (No, 0.'J(>0). Thus there may be only two maxillary series, and the 

 su])erciliary row may not be distinctly divided. There are two rows 

 along the superior part and two rows along the inferior part of the 

 lower jaw. 



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