Dr. J. E. Gray on new Genera of Lizards. 101 
he heard from the gentleman. The leg, when I saw it, looked fresh 
where it had been cut off. 
(Signed) « Henry STEVENSON.” 
It will be remembered that Mr. Darwin, in his work on the 
‘ Origin of Species,’ speaks of the possibility of the seeds of plants 
being occasionally transported to great distances by being enclosed 
in earth adhering to the beaks and feet of birds; and he mentions 
the fact of his having “removed twenty-two grains of dry argillaceous 
earth from one foot of a Partridge,” in which earth “ there was a 
pebble quite as large as the seed of a vetch”’ (pp. 362, 363). Now 
the mass of clay I exhibit is enormously greater than the quantity of 
earth mentioned by Mr. Darwin, and is sufficient to hold the germs 
of a very extensive flora. 
Apart from the statement of Mr. Stevenson, that the lump, when 
he first saw it, was “as hard as stone,’ and the contrast thereby 
afforded by the “ fresh look” of the leg, a close examination of the 
specimen convinces me that the clay, as that gentleman suggests, ac- 
cumulated gradually. The two toes which are visible have become 
distorted, and have accommodated themselves as well as they were 
able to the shape of the mass. I imagine also that the loss of the 
claw, noticed by Mr. Stevenson, has been experienced since the mass 
attained nearly its present size and shape; and it will be seen that 
the stump has perfectly healed over. Now all this must have taken 
some time ; I do not venture to say whether days, weeks, or months. 
It is clear that, as the bulk and weight of the encumbrance increased, 
it would more and more interfere with the bearer’s means of obtain- 
ing a livelihood ; and hence, weakened by starvation, the bird was 
finally unable to rise, and met its death in the manner stated. 
If, as I believe, the clay accumulated by degrees, it is obvious that 
there was once a time when the incipient mass was no heavier a bur- 
then than the bird was able to bear in flight. What the actual limit 
was, is a question we have no means of determining; at least I am 
not aware of any experiments having been made tending to show 
what weight a Partridge is capable of supporting on the wing. But 
I trust I have said enough to justify me in bringing this before the 
Society as a singular illustration of the manner in which birds may 
occasionally aid in the dispersion of seeds. 
Descrivtions oF Two New Genera or Lizarps (Hotaspis 
AND PortopoGasTER, A. SmitH, MS.). By Dr. J. E. 
Gray, F.R.S., etc. 
Sir Andrew Smith, M.D., having most kindly sent to the collection 
of the British Museum two most interesting Lizards, which he has 
very properly named as the types of two new genera, I hasten to 
send to the Society a short description of each of them under the 
MS. names which Sir Andrew Smith has attached to them in his 
museum. 
The first genus is allied to the family Lacertinide, and is at once 
known from all the genera of that group by the peculiarity of having 
