TWO NEW EMBIID.E. 23 



One of the Embias was kept in a small culture dish with a few 

 grains of sand. The first night it spun along the edge of the 

 glass a web in which it remained the two following days. Then 

 it discovered the sand in the center of its room and spun another 

 gallery between the surface of the glass and the sand. In this 

 position it was absolutely concealed, having completely covered 

 the web with the small amount of sand present. Einbia is ex- 

 clusively nocturnal, at least in the nymphal state. Although the 

 tunnel was in great part completed in a single night additions 

 were made to it on several succeeding nights. 



At first sight the silk resembles a very thin, pale gossamer, 

 but when viewed under a strong magnification the individual 

 threads are seen to be arranged in fine bundles of varying thick- 

 ness. Most of the threads in a bundle lie parallel with one an- 

 other, but the bundles contain a few curled threads also. The 

 individual threads vary in diameter. 



In making its web Einbia does not use its mouth notwith- 

 standing Hagen's statement that spinning organs are present 

 among the mouth parts but it uses instead, its forefeet, as 

 Grassi had shown. No other animal has developed spinning 

 organs in this position. The silk is produced by large glands 

 occupying nearly the whole of the enlarged metatarsus. The 

 underside of this joint is provided with a dense mat of small 

 short bristles, and interspersed among them are the longer 

 spinning bristles, each of which is hollow and slightly re- 

 curved at the tip and contains a tenuous duct from the gland. 

 While spinning, Einbia very rapidly moves its forefeet, either 

 singly or both together, now reaching out directly in front, 

 now to the side, with a movement which reminds one of a 

 cat toying with a string. Each time it touches a surface it 

 attaches a bundle of silk. As the bundles are of varying sizes 

 it would seem that sometimes all the glands function, at others 

 only one. 



While spinning its cylindrical retreat, Einbia slowly rotates 

 on its longitudinal axis. When within its nest it does not 

 find it inconvenient to rest with head downward. It was seen 

 resting on its side or back more frequently than with its ventral 

 surface down. The soothing touch of its web seems to be suffi- 



