The members of the families constituting the Cri bellâtre — 

 that is, those spiders having a cribellum and a calamistrum — 

 spin viscid threads that are distinctively characteristic in being 

 flat and more or less ribbon-like structures. To threads of this 

 form I have applied the term liackled bands. 



The structure of the hackled bands difters in difterent families, 

 and sometimes in diñerent genera of the same family. But in 

 all that I have examined the band consists of two elements : 

 first, two or four longitudinal strands, the supporting part of 

 the band — this may be termed the warp ; and second, a viscid, 

 sheet-like portion supported by the warp — this may be termed 

 the woof. 



The hackled bands that most closely resemble the viscid 

 thread of the Ar gio pides are those spun by members of the Ulo- 

 horidœ, whose webs also bear a striking resemblance to those 

 of the ArgiopidcB. In these webs the hackled band occupies a 

 similar position to that occupied by the viscid thread of the 

 Argiopids ; but the method of fastening it to the radii is 

 different. This is well shown in the web of Hyptiotcs, where it 

 can be seen that the hackled band is attached lengthwise to 

 each radius. 



The structure of the hackled band of Hyptiotes is shown by 

 Fig. 6. It consists of a warp of two straight strands, which 

 support a series of overlapping lobes of viscid silk. It is evident 

 that this silk is much less fluid than that of the Argiopids, for it 

 retains its form, which was probably given to it by the combing 

 action of the calamistrum. It is inferred that this viscid silk 

 is produced by the cribellum glands. 



The hackled band of Aniaurohius (PI. IV, fig. 7), which can be 

 taken as an illustration of that of the Dictynidœ, differs markedly 

 from that of Hyptiotes. In this band the warp consists of four 

 strands, two of which are straight, and two are greatly curled. 

 The woof is a wide, flat sheet of viscid silk, the margins of which 

 have a wavy outline. But there is little to indicate that this 

 silk owes its form to a combing action of the calamistrum, as 

 is the case in the hackled band of Hyptiotes. It may be that 

 the two curled threads of the warp owe their form to this action, 

 but I think this is hardly probable : the loops in these threads 

 are so numerous that it would require an exceedingly rapid 



