76 COLUBERCONSTRICTOR. 



narrower externally, where they pass in behind the nasal plates; the anterior 

 frontals are subround; the rostral is rather elongated and pointed anteriorly, and 

 is very regularly triangular, with its basis down and its apex upwards; there 

 are two nasal plates, of which the anterior is quadrilateral and slightly concave 

 behind; the posterior is nearly of the same size and form, but more semi-lunated 

 or crcscentic on its anterior margin, to accommodate the nostril; there are two 

 anterior orbital plates, the inferior small, the superior very large, making a 

 considerable portion of the front of the orbit, and then ascending between the 

 frontal and superior orbital s to the same horizontal plane as the frontal plate; 

 in front of it is a square loral plate, which joins it to the posterior nasal; there 

 are two small posterior orbital plates, the upper is irregularly quadrilateral, the 

 inferior is semi-lunated or crescentic; there are seven large irregularly quadri- 

 lateral labial plates on each side, increasing in size from the snout to the angle 

 of the mouth, the third and fourth of which make the inferior wall of the orbit of 

 the eye. The nostrils are lateral, very large and near the snout. The eyes are 

 large and bright; the pupil black, and the iris of the darkest grey. The neck is 

 contracted. 



The body is very long, slender, and covered with large smooth hexagonal 

 scales above, and with broad plates below. The tail is equally long and slender, 

 and at times may be used as a prehensile instrument. 



Colour. The whole superior surface of the Coluber constrictor is of beautiful 

 bluish-black; the abdomen and tail are bluish-slate; while the chin and throat are 

 pure silvery-white, sometimes marked with a few black spots. 



Dimensions. Length of head, 1 inch 8 lines; length of body, 47 inches; length 

 of tail, 16 inches; total length, 5 feet 3 inches and 8 lines. In the specimen 

 above described there were 176 broad abdominal plates, with a double one before 

 the vent, and 94 scales under the tail. These snakes are said at times far to 

 exceed these dimensions; the longest I have ever seen was 6 feet 1 inch. 



