246 Miscellaneous. 



Trigonocephalus Landshei'gii, Schl., Bothrops Castelnaudi, and 

 Bothrops alternans, D. & B., have not yet come under my notice. 



Of Craspedocephalus bilineatus I have seen eight specimens — seven 

 from the vicinity of Villa Vicosa (where the Prince of Wied, viho 

 first described the species), found his specimen, and one of unknown 

 origin. 



1 had previously observed that some Brazilian species of Snakes 

 (as Spilotes variabilis and S. jjoecilostoma, Coryphodon pantherinus, 

 Xenodon colubrinus, &c.) have the habit of striking the ground 

 rapidly with their tail when irritated ; I had lately occasion to 

 notice the same peculiarity in a large specimen of Craspedocephalus 

 atrox. 



MISCELLANEOUS. 



Additional Observations on Chelymys dentata. 

 By Dr. J. E. Gray, F.R.S. &c. 

 In the previous Number of the 'Annals' (p. 98), I described a new 

 species of Chelymys, from the Upper Victoria River, brought to 

 England by my late friend Mr. Elsej'-, and not by INIr. Macgillivray, 

 as inadvertently stated in that paper. 



When I made that description, I had forgotten that we had also 

 an adult specimen, brought from the same locality at the same time, 

 which is doubtless the adult of this species ; and this specimen proves 

 that the dentated form of the margin is only a peculiarity of the 

 younger state of the species ; and therefore the specific name is not 

 one that I should have chosen if I had had the adult form of the 

 species before me when I selected it. But as the margin is not 

 dentated in the young of the other species, it is still characteristic. 

 The species is easily known from the other, both in its adult and 

 young state, by the absence of the nuchal plate. 



The adult shell is oblong-ovate, solid, and high ; the back is worn 

 smooth, and the margin is entire, the edge over the legs being rather 

 expanded, and the hinder part over the tail rather inflexed; the 

 vertebral plates are very long, slender, with straight parallel sides, 

 nearly twice as long as they are wide ; the hinder part of the fourth 

 shield is rather narrowed. The sternum is narrow, rounded in front, 

 and with a deep semicircular notch behind, high on the sides. The 

 underside is black, with a few unequal-sized yellow blotches. The 

 length is 13 inches ; width over the back 10| inches. 



On a New Genus of Humming-Birds. 

 By John Gould, F.R.S. 



To the Editors of the Annals and Magazine of Natural History. 



Gentlemen, — I send for insertion in your next Number a de- 

 scription of a new and very singular Humming-Bird which I have 

 lately received from Ecuador. Not only does it differ specifically 

 from every other with which I am acquainted, but it also differs in 

 its structure from every form comprised in the great family of Tro- 

 chilidse. I therefore propose to call it 



