136 RECORDS OF THE AUSTRALIAN MUSEUM- ^ ■ 



The calamistrum or comb is situated upon the upper side of 

 the metatarsus of each of the fourth pair of legs, and consists of 

 two parallel rows of short stiff bristles or spines. This organ is 

 used for combing or carding the flocculent silk emitted by the 

 cribellum. ■ :'-' ^ '■■'■ 



Fig. 16. — The Calamistrum. 



The cribellum and calamistrum are always present in the female. 

 Young males are also provided with them, but towards maturity 

 they become in some cases atrophied, and in others disappear 

 altogether. 



Orihellate Spiders are of sedentary habits, and are therefore 

 dependent upon their webs for the capture of prey. These snares 

 vary according to the habits of the species, some being of an orb- 

 like or geometrical construction, with rays and concentric circles, 

 and others of an irregular design. Some of the Spiders of this 

 section are arboreal, living amongst coarse herbage, the leaves of 

 shrubs and trees, or upon bark ; others lurk within crevices, fissures 

 of rocks, and inside buildings; whilst others disfigure the outer 

 walls with their untidy, dirty-looking webs. Indeed more serious 

 annoyances occur at times, owing to the habit of these and other 

 Spiders of attaching their webs to telegraph wires and poles, thus 

 interfering with the transmission of messages. Railway telegraphs 

 have been interfered with in this and other countries, and the 

 authorities put to considerable trouble and expense to keep the 

 wires clean and free. 



Snares are composed of two kinds of silk — the one strong and 

 tough, the other soft and flocculent. The former is used in the 

 construction of the framework, whether the lines be those of an 

 orb or an irregular web, and is discharged from the ordinary 

 spinnerets; the flocculent silk is voided by the cribellum, and 

 is attached to the lines forming the framework. But before 

 being attached, it has to pass through the process of combing, 

 and the method by which this is accomplished is interesting. 

 One of the posterior limbs is held up and passed just under 

 the cribellum, and as the silk is emitted, worked rapidly 

 backwards and forwards. When one limb becomes wearied, the 

 other relieves it, and so on until the completion of the snare. 



