132 
droma wilsoni and Mergus cucullatus European birds ; but because 
a single individual of Regulus calendulus or*Dendreca virens has 
reached the Old World, it is absurd to include either of those species 
in its Fauna. I cite these instances, because they ave all from that 
continent whence most of our occasional visitants arrive ; so much 
so, that one is almost driven to the conclusion that there is no primd 
JSacie reason why examples of the greater number of birds of Eastern 
North America should not, favente zephyro (the prevailing strong 
wind in Western Europe), make their appearance on our shores in 
course of time. Then, on the other hand, the last two additions to 
the list of so-called “ British birds”? have been from the opposite 
quarter. Are Syrrhaptes paradoxus and Xema ichthyaétus to take 
their places in the books elucidating British Ornithology by the side 
of the Red Grouse and the Peewit Gull? It appears to me that we 
gain nothing by deferring a decision on the subject, and I trust that 
these remarks will not be deemed unnecessary by those who are 
competent to deal with the matter. 
Elveden, 28 February, 1860. 
4, DrescripTION or A New Genus or Boip& DISCOVERED BY 
Mr. Bates oN THE Upper Amazon. By Dr. J. E. Gray. 
(Reptilia, Pl. XXIV.) 
Fam. Borpz. 
CHRYSENIS, 0. g. 
Head rather large, rather depressed, covered with scales, the front 
half covered with small symmetrical shields, as follows :—two pair 
in an arched series behind the rostral and nasal, and four pair forming 
a ring round the pair of small central frontal shields ; loreal shields 
two; eyes surrounded by a series of small shields, with a series of 
four or five small superciliary shields above them; forehead, crown, 
and cheeks covered with small granular scales; rostral plate with a 
pit on each edge ; upper labial shields low, with a large deep pit on 
their hinder edge ; front lower labial shields simple, high, the hinder 
short, with a very deep pit on the hinder edge of each of them; 
nostrils situate between two moderately sized, nearly equal, nasal 
shields ; pupils erect, oblong ; body compressed, rounded above and 
below ; tail conical, with a single series of subcaudal plates. 
This genus resembles Epicrates as to the shields on the muzzle, 
but differs in the distinctness and form of the pits on the labial 
shields. 
Curysents BaTesit (Pl. XXIV.). 
Pale brown, with a series of oblong subangular black-edged pale 
spots on the hinder part of the back, which become broader and 
more distinet,as they approach the end_of the tail, and with a series 
of distant small roundish black-edged spots on the lower part of the 
