76 



ARACHNOIDEA. 



CASE are all composed of simple threads ; (more correctly, of threads 

 composed of many strands, which become entirely united), whereas 

 the web of the Ciniflo is a loose, irregular open net, formed of 



f^^^i 



Fabric of the web of the Ciniflonids. 



flocculous compound threads. These are very beautiful under 

 the microscope. One straight line usually forms the foundation of 

 the compound thread, and this is accompanied by several lines of 

 extreme fineness, some of which are merely slack, while the rest 

 are curled and twisted in every direction, by the operation of the 



spines forming the calamistrum. 

 When newly spun, these threads 

 have to the naked eye a bluish 

 colour, but being very apt to en- 

 tangle dust, the net is most fre- 

 quently found in a foul and dis- 

 coloured state. When handled, it 

 clings to the fingers with remark- 

 able tenacity. This is said to arise 

 from the structure, rather than from 

 any peculiar viscidity of the thread. 

 The bluish colour of the web has 

 been already noticed, and viewed in 

 the microscope with the help of the parabolic condenser, the com- 

 pound thread appears to be enveloped in something like a bluish 

 cloud or vapour. Whatever this substance may be, (and it is so 

 transparent as easily to escape observation under even the most 



Calamistrum of Ciniflo 

 (enlarged). 



Part of ditto 

 (more magnified). 



