XXlv. Proceedings. 
of the various species of ants, contrasting them with bees. He 
also alluded to their propensity for eating flesh, and explained 
how by the agency of ants, good skeletons of small animals 
could often be obtained. In proof of this he took up the skull 
of an animal which was lying on the table, and which had been 
cleaned in a most beautiful and effectual manner by those 
insects. In the piece of the laburnum tree which was 
exhibited, the arrangement of the nest was seen in a very clear 
manner. Unfortunately the tree had been split open before 
the existence of the formicarium was discovered. A portion of 
the nest had been sent to the British Museum. The remainder 
was before the meeting. Thecovered ways, the winding stair- 
case like passages, and the extensive apartments in which the 
eggs of the ant were stowed away, and moved about, were very 
manifest. It would appear that the ant was an acute observer 
of the state of the atmosphere, that, without either barometer 
or dew point measure other than those existing on their own 
persons, they were able to judge as to the kind of day in 
store for them, and used to arrange their eggs and pupa 
. accordingly, with almost unerring certainty. Dr. Carpenter 
also called attention to the walls of the nest, which were 
arranged so as to limit the action of cold and moisture to the 
fullest extent. 
In the discussion which ensued, 
Mr. W. H. Rowrtanp asked whether the water-rat, in 
addition to living upon vegetable matter, did not also eat fish. 
When he had been snipe shooting he had found pieces of cray- 
fish shell which had apparently been eaten by water-rats, and 
he thought that in addition to vegetable matter these rats 
indulged in food of this kind. 
The PRESIDENT said that about almost every river, especially 
if near a town, there were two kinds of rat—the water-rat 
(Arvicola amphibia), and the common brown rat (Mus decu- 
manus). The latter was very fond of water, and was constantly 
seen upon river banks, and would eat anything. The water- 
rat on the other hand was more like a beaver, and as a rule 
lived upon vegetable food only. He was very much inclined 
to think that the cray-fish referred to by Mr. Rowland had been 
eaten by the common brown rat, and not by the water-rat. 
The two were very often confused, but they were very distinct 
animals in their habits and their structure. 
The PresipEenT called particular attention to a very inte- 
resting series of nests, 47 in number, exhibited by Mr. P. 
Crowley, in each of which a cuckoo had laid its egg. (These 
were again exhibited at the meeting on April 16th. See p. 38). 
He also called attention to a skull, to which Dr. Carpenter had 
