SPIDERS : THEIR STRUCTURE AND HABITS. 125 



thin, straight Hnes, with a tortuous Hne superposed on each ; and 

 on each of these again a pale-blue band, of such extreme tenuity 

 that its filaments are imperceptible, even by the aid of the 

 microscope. These blue bands impart to the web an adhesive 

 character, — not from being glutinous, but from their fibrous nature, 

 since they are composed of loose fibre Uke floss silk. These 

 composite flocks are produced by the use of the calamistra, which 

 are so beautifully regulated in position and movements that the 

 points of the lower row of spines draw out the filaments from the 

 tips of the spinnerets, while the upper row detach them by an 

 upward movement. Each flock, as soon as completed, is fixed to 

 one of the foundation-Hnes. 



There can be little doubt that, in constructing this web, the 

 long pair of spinnerets is used to produce the foundation-lines ; 

 the upper intermediate pair produce the two fine, straight fines, 

 and the lower intermediate pair the two tortuous ones ; while the 

 fourth pair, with their innumerable papillse, produce the pale-blue 

 bands. On this hypothesis, the relative position of these various 

 components of a flock, as well as their several characters, is best 

 accounted for. 



I have alluded to the strong maternal instinct of these crea- 

 tures as an amiable feature in their character, and it may not be 

 uninteresting to bestow some brief notice upon the way in which 

 they exercise their parental functions. 



The period of the year when the female deposits her eggs 

 Varies in different families, and embraces all the months from 

 May to October inclusive. At the proper time she prepares a 

 cocoon, and sometimes more than one, in which to deposit them ; 

 and these cocoons differ much in form, colour, texture, situation, 

 and contents. Two examples of the process employed will 

 suffice for present illustration. 



The Epeira quadrata, in constructing her cocoon, (a single one,) 

 presses her spinnerets against the mass of eggs, and attaches a 

 compound line to it ; then, drawing out the line by raising her 

 body, she again attaches the spinnerets to the eggs, and cements 

 this line to them in the form of a small loop. This operation is 

 continued until the eggs are covered ; when the lines are united 

 and form a mass of short silken loops, giving the cocoon a loose 

 texture. 



Others of a more compact structure are fabricated in the 

 following ingenious manner : — The mother spins a thin coating of 

 silk, and gives it a hemispherical shape by turning her body round 

 and round during the process. The hollow cup thus formed she 

 fills with eggs, piling them up till they become a globe, of which 

 the upper half is bare. Over this she spins another coating 



