56 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



At times, when the female approached him as he danced, he was seen 

 to make attempts to enclose her in his great chelate arms, not with any 

 violence, for the claws never snapped or closed violently. She was coy, 

 however, and refused to be won by his advances ; for the dance may have 

 been nothing new to the lady crab, nor half as interesting as it was to the 

 two spectators outside the water. Later the male also buried himself in 

 the sand, and the performance came to an end. 1 



The love dances of Saltigrade spiders also suggest a similar habit record- 

 ed of certain birds. Familiars of our American woods and fields will recall 

 the well known partridge dances. Among the Chatterers the beau- 

 Love tiful bird known as the Cock of the Rock (Rupicola rocia) is 

 famous for its saltigrade performances at the mating time. In- 

 deed, the action of our domestic -pigeons and barnyard fowls, 

 although not so decided as these, yet suggest a like tendency. 2 



Mr. Wallace has given an account of similar actions by the beautiful 

 Birds of Paradise in the Aru Islands. They moult about January or Feb- 

 ruary ; and in May, when in full plumage, the males assemble in the morn- 

 ing to exhibit themselves in a most singular manner. These are what are 

 called their " sacaleli," or dancing parties, and they occur in certain trees in 

 the forest, which are not fruit trees, but have an immense head of spread- 

 ing branches and large but scattered leaves, giving a clear space for the 

 birds to play and exhibit their plumes. On one of these trees a dozen 

 or twenty full plumaged male birds assemble together, raise up their wings, 

 stretch out their necks, and elevate their exquisite plumes, keeping them 

 in a continual vibration. Between whiles they fly across from branch to 

 branch in great excitement, so that the whole of the tree is filled with 

 waving plumes in every variety of attitude and motion. 



The bird itself is nearly as large as a crow, and is of a rich coffee 

 brown color. The head and neck are a pure straw yellow above, and rich 

 metallic green beneath. The long, plumy tufts of golden orange 

 Displays f ea thers spring from the sides beneath each wing, and when the 

 T>- d < bird is in repose are partly concealed by them. At the time of 

 Paradise. ^ s excitement, however, the wings are raised vertically over the 

 back, the head is bent down and stretched out, and the long plumes 

 are raised up and expanded until they form two magnificent golden fans, 

 striped with deep red at the base, and fading off into the pale brown tint 

 of the finely divided and softly waving points. The whole bird is then over- 

 shadowed by them, the crouching body, yellow head, and emerald green 

 throat forming but the foundation and setting to the golden glory which 

 waves above. When seen in this attitude the Bird of Paradise really 



1 T. II. Morgan, Popular Science Monthly, February, 1889, "The Dance of the Lady Crab." 



2 For further material on the display of their charms by the males of birds see Darwin's 

 Descent of Man, Vol. II., chap, xiii., Am. Ed. 



