Character of two Genera of African Reptiles. 141 
Alopecurus fulvus. A careful examination of this plant and A. 
geniculatus, has shown me the following distinctions between them : 
A. fulvus. Flowers one-third less than those of A. geniculatus ; 
palea as long or longer than the glumes; awn inserted just below 
the middle of the palea, and slightly longer than it ; anther short 
and broad. Sheaths of the leaves white between the ribs, with very 
minute hoary granules. Panicle very long. 
A. geniculatus. Palea shorter than the glume ; awn inserted near 
to the base of the palea, and twice its length; anther linear. Sheaths 
of the leaves without hoary granules. Panicle shorter. 
Festuca dmiuscula, y. hirsuta. F. hirsuta, Host. ? Root black, 
fibrous. Radical leaves setaceous, glaucous, half as high as the 
stem ; stem leaves involute ; sheaths three or four times as long as 
the leaves. Stem obsoletely quadrangular, covered with very mi- 
nute down. Spikelets four or five-flowered. Glumes hairy ; ex- 
ternal palea very densely pubescent, internal glabrous, with its 
margin ciliated ; anthers two or three times as long as their fila- 
ments. 
I have drawn up the above description of this plant on account of 
its not having been noticed in any work on the plants' of this coun- 
try. Gathered on the summit of Pen y Gader, the highest summit 
of Cader Idris, Wales, July 1832. 
Poli/podium calcareum may always be distinguished from P. dry- 
opteris by being minutely mealy in all its parts. Each particle of 
this mealiness, under a high magnifying power, appears to be a mi- 
nute stalked gland. I have not been able to find any trace of this 
on P. dryopteris. 
IV. The Characters of trvo new Genera of South African Reptiles, 
with descriptions of species belonging to each. By ANDREW 
SMITH, M. D., M. W. S., &c. 
IN the year 1825, I first obtained the Cape species of the genus 
Chrysopelea, and on examining it, I observed some peculiarities of 
formation which were not exhibited by any of the genera of serpents 
with which I was acquainted. From that circumstance, I was im- 
mediately led to set it apart as a type for an additional division, and, 
from the singular manner in which the abdominal plates were form- 
ed or apparently divided, I constructed the term Aspedotrischedis 
to designate the new genus. 
Soon after that I had a visit from my late friend, the lamented 
M. Boie, on his way to Java, when I substituted the name Chry- 
