1881.] NATURAL SCIENCES OF PHILADELPHIA, 433 



traverse in passing from the top of one of the forks to a simihir 

 point on the opposite one. presented comparativeh' few difli- 

 culties. But no attempt was made to carry the line around, and 

 as the wind had evidently not chansed during the night, no web 

 appeared upon the ti'ee in the morning. During the next evening 

 the same restless movement along the bare limbs of the sapling 

 was repeated, and was terminated at a late hour by a rare 

 accident. A large moth, attracteil by the lantern, became entau 

 gled upon a single short thread stiung between two small twigs, 

 Avhereupon Strix pounced upon it. swathed and fell to feeding on 

 it. Next morning a tim^ orlj-web had been built around the shell 

 of the moth at the point of capture. 



During both evenings this spider at frequent intervals poised 

 herself at the extremity of twigs, and emitted threads from her 

 spinnerets which entangled upon some of the short twigs, but 

 never upon the opposite fork, as the wind was steadily contrary. 

 No other entanglement was secured, as there was no object in the 

 direction of the wind for a great distance. However, Dr. 

 McCook could, at any time, obtain an entanglement upon his 

 hand b}'^ arresting the thread. By imitating the motion of a 

 swaying leaf or limb, the spider was caused to perceive the 

 attachment, and immediately ventured upon the line. Once the 

 thread fastened upon the observer's face, and the animal was 

 allowed to cross the line (four or five feet) until within a few 

 inches of the face, when she took in the situation, instantly cut 

 the line and swung downward and backward over the long arc, 

 and, after a few oscillations, climbed up the line to the point of 

 departure. Her willingness to use the air-currents for making 

 transit lines was thus quite as manifest as her inability. The 

 third spider exhibited a like behavior. 



4. The third individual, a male, did not attempt to spin an 

 orb in the former site ; the wind was unfavorable, but there would 

 not have been much difficulty in carrying a cord around. He came 

 out of his rolled-leaf den at 7.20 P. M., and for more than an hour 

 labored to secure a web foundation. He was located upon a dead 

 v'^nd of a bough of a tree, with man}' branching twigs. As with 

 the former individual, so with this ; many efforts were made to 

 obtain foundations by sending out threads fi'om the spinnerets, 

 and to this end he tried most of the numerous i)oints of the 

 twigs covei'ing the territory which he seemed to have chosen as 

 his general range. One of these, a little pendant which hung in 

 the centre of the group, was taken as the basis of a most intei-- 

 e'sting operation. The spider dropped from the pendant by a 

 line three or four inches long, grasped the line by one of tlie 

 second pair of feet, and rapidly formed a triangular basket of 

 threads by connecting the point of seizure with lines reaching to 

 the feet of the remaining second and the third and fourth jxairs. 

 Ill this basket he hung head upwards, the bodj^ held at an angle 



