1894.] Psychology. 899 
those of strife, for first one and then another would act the pursuer and 
the pursued. There were, generally, four or five actinophryans in the 
game. One of the rotifers frequently acts as if engaged in play. On 
several occasions I have observed them perform a kind of dance, a pas 
seul, for each rotifer would be alone by itself. Their motions were up 
and down as if exercising with an invisibleskipping-rope. They would 
keep up this play for several minutes and then resume feeding or 
quietly remain at rest. This rotifer goes through another performance 
which I also believe to be simply a pastime. Its tailis armed with a 
double hook or forceps. It attaches itself to a piece of alga or other 
substance by this forceps, and then moves its body up and down in the 
water for several minutes at atime. The snail (H. pomatia) likewise 
has its moments of relaxation and amusement. The following instance 
of play may be considered to be gallantry by some, but I do not believe 
that I am mistaken, however, when I consider it an example of animal 
pastime. Two snails approproached each other, and, when immedi- 
ately opposite, began slowly to wave their heads from side to side. 
They then bowed slightly several times in courtly salutation. This 
performance they kept up for quite a while and then moved away in 
different directions. At no time did they come in contact, and careful 
observation failed to reveal any excitement in the genitalia. I have 
witnessed the embraces of snails, and the performance described above 
does not resemble in the slightest degree, the manouvres executed at 
such times by mating individuals. 
Swarms of Diptera may be seen on any bright day dancing in the 
sunlight. Naturalists have heretofore considered this swarming to be 
a mating of the two sexes. This is not the case, however, in many 
instances. On numerous occasions, and at different seasons of the year, 
I have captured dozens of these insects in my net and have examined 
them microscopically. I found them all to be unimpregnated females ; 
l have never yet discovered a male among them. In some of the 
Diptera the males emerge from the pupa state after the females; I 
therefore believe that the females await the presence of the males, and, 
while waiting, pass the time away in aerial gambols. 
Forel, Lubbock, Kirby, Spence and other naturalists have declared 
that ants, on certain occasions, indulge in pastimes and amusements. 
Huber says that he saw a colony of pratensis, one fine day, “ assembled 
on the surface of their nest, and behaving in a way that he could only 
explain as simulating festival sports or other games." On the 27th of 
last September, the males aud females of a colony of Lasius flavus 
emerged from their nest; 1 saw these young kings and queens con- 
