M. Charpciitier on the Erratic Phenomena of the North. 55 



scuta near the anus have their posterior edges black, and the 

 divided scuta of the tail are deeply edged with the same hue. 

 The plates protecting the head are nine, of the normal shape ; 

 the vertical plate is middle-sized ; the temporals are rather 

 large ; the occipitals very large ; the posterior frontals are 

 considerably larger than the anterior pair ; the superciliaries 

 are large ; the rostral is rounded, and emarginate below ; 

 each nasal plate has a sulcus, in which are placed the open, 

 lateral nostrils ; the frenals are wanting. There are four pos- 

 terior and three anterior orbiter plates. There are eight su- 

 perior and ten inferior labial plates. 



The eye is rather large and prominent; the pupil orbicular. 



The fangs are slender, and have a distinct longitudinal fur- 

 row on their anterior convex surface, as in Schlegel's first 

 subdivision of venomous serpents. They are attached to the 

 maxillary bones, which are, as usual in venomous snakes, 

 moveable by muscles attached to the pterygoid bones. The 

 poison-gland, placed at the angle of the jaw, is covered by a 

 firm albugineous tunic, has a cellular structure, and sends off 

 a slender poison duct, in the usual manner, to the root of the 

 fangs. 



These particulars are noticed to shew that this serpent 

 really belongs to the true venomous snakes, not to the Lyco- 

 dons, with which a superficial view might readily confound it, 

 as it has several analogies with that genus of harmless ser- 

 pents. 



Edinburgh University, March 19. 1842. 



On the Application of the Hypothesis of M Fenetz to the Er- 

 ratic Phenomena of the North; a Letter addressed to M. 

 Macaire, Counsellor of State, by M. Jean de Charpentier* 



Sir — You have been good enough to take the trouble of 



* From the Bibliotbeque Universelle de Geneve, No. 78. As we have 

 all along endeavoured, so far as our space permitted, to convey to our 

 readers full information respecting glaciers, and the topics more imme- 

 diately connected with them, we collected, at p. ICO of vol. xxx., references 

 to the most important papers which liad appeared in this Journal on the 

 subject ; and we now continue that list, premising the titles of some shorter 



