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2. Zoological Society of London. 
3th April, 1883. — The Secretary read some extracts from a letter 
he had received from Mr. J. Sarbo in reference to the Gayal. The writer 
observed that Bos gaurus (the Gaur) and not Bos frontalis (the Gayal) is the 
Wild Ox of Assam, and that the B. frontahs is not known in a wild state, 
but only as a semi-domesticated animal owned by various wild tribes from 
Assam to Arracan. — Mr. Sclater called the attention of the Meeting to 
the skin of a Brown Crow from Australia, which had been sent to him for 
examination by Mr. Albert A. C. Le Souef, C.M.Z.S., and which he was 
inclined to regard as a variety in plumage of Corvus australis. — Mr. A. G. 
Butler read a paper containing an account of a collection of Indian Lepi- 
doptera made by Lieut.-Col. Charles Swinhoe, chiefly at Kurrachee, Solun, 
and Mhow. Thirty-two new species were described, and numerous field- 
notes by Col. Swinhoe were incorporated in the paper. — Col. J. A. Grant 
read some notes on the Zebra met with by the Speke and Grant Expedition 
in the interior of Central Africa in 1860—63, which certainly belonged 
either to the true Zebra (Equus zebra) or to its closely allied northern form, 
the recently described Equus Grevyi. — P.L.Sclater, Secretary. 
i 3. Linnean Society of London. 
19th April, 1883. — A paper was read by Sir John Lubbock 
,On the sense of Colour among some of the Lower Animals‘. He said, some 
years ago M. Paul Bert made a series of interesting experiments with the 
common daphnia or water flea which is so abundant in our ditches and pools ; 
he exposed them to light of different colours and he thought himself justified 
in concluding from his observations that their limits of vision at both ends 
of the spectrum are the same as our own being limited by the red at one 
end and the violet at the other. In a previous communication Sir John 
Lubbock showed that on the contrary they are not insensible to the ultra 
violet rays and that at that end of the spectrum their eyes were affected by 
light which we were unable to perceive. These experiments have recently 
been repeated by M. Merezkowski who however maintains that though 
the Daphnias prefer the yellow rays which are the brightest of the spectrum 
they are in fact attracted not by the colour but by the brightness; that — 
while conscious of the intensity of the light they have no power to distin- 
guish colours. Given an animal which prefers the brightest rays, it may seem 
difficult to distinguish between a mere preference for light itself rather than 
for any particular colour. To test this however Sir John Lubbock took 
porcelain troughs about an inch deep 8 inches long and 3 broad. In these 
he put 50 daphnias: and then in a darkened chamber threw upon them an 
electric spectrum arranged so that on each side of a given line the light was 
equal, and he found that an immense majority of the Daphnias preferred the 
green to the red end of the spectrum. Again to select one out of many ex- 
periments he took four troughs and covered one half of the ist with a 
yellow solution, !/ of the 2nd with a green solution, '/, of the 3d with an 
opaque plate and he threw over one 1/2 of the fourth a certain amount of 
extra light by means of a mirror. He then found that in the first trough a 
