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males take floating insects of all kinds — sometimes specially 

 Diptera, sometimes Aphids — scales on overhanging trees or 

 other fragments of plants. Some of the species will accept almost 

 any floating object, while others seem to restrict themselves to 

 particular insects, such as Aphidcp. When the object is very 

 heavy the male, after seizing it, spins round with great v'elocity 

 till the load rises on a cone of water and is finally lifted from the 

 apex. In Mr. Hamm's experiments disabled Diptera of the genus 

 Chironomus, etc., stamens of buttercups, and ray florets of daisies 

 strewn on the water were soon taken by the males and afterwards 

 found in the possession of the females. Pairing invariably occurs 

 upon the wing, but numbers of specimens show that a sweep of the 

 net through the swarm at first catches nothing but males carrying 

 the objects that had been strewn on the water, while a later 

 sweep catches pairs still carrying the same objects. The speci- 

 mens illustrating the investigation are all carefully labelled with 

 the hour and minute at which the different samples were secured. 



" Mr. Hamm's admirable experiments also enabled him to 

 determine that the females carry the objects provided by the 

 males ; for although they are never retained when the pairs 

 are captured, the white florets or the yellow stamens can be 

 seen hanging from the lower Hilara of each flving pair, and 

 the lower is invariably the female. 



" The climax is reached in the males of certain species of Hilara 

 which envelop the prey or other minute object in a cocoon, 

 varying greatly in complexity, but in the most extreme cases of 

 striking beauty and regularity. The cocoon is spun upon the 

 wing, so that the method of its construction cannot be followed. 

 Captured individuals are often found to have extruded a viscid 

 globule — probably the material out of which the cocoon is spun. 

 There can be little doubt that in these extreme cases it is the 

 cocoon itself which acts as a stimulus to the female, although the 

 minute and almost invisible object usually enclosed in it, but some- 

 times dropped, is the stimulus which incites the male to spin. 

 Cocoons that have been dropped, probably after pairing, are 

 constantly picked up and used over again by other males. 



"These novel and surprising conclusions, obtained as the 

 outcome of Mr. Hamm's energy, resource, and power of accurate 

 observation, are illustrated and confirmed by an immense mass 



