STRUCTURE AND ECONOMY OF SPIDERS. 319 
four only ; individuals which have attained nearly a 
third of their growth have five or six; those about 
two-thirds grown six or seven; and adults, which 
have acquired their full compliment, eight—two of 
them, situated on the inferior surface of the spinner, 
at a greater distance from its extremity than the 
rest, are minute and almost contiguous. It is a fact 
deserving of notice that the papille are not always 
developed simultaneously on these spinners, six, seven, 
or eight being sometimes observed on one, when five, 
six, or seven only are to be seen on the other; and 
this remark is applicable not to the inferior spinners 
alone, but to the intermediate ones also, which, in 
mature individuals, are further modified by having 
the extremities of the terminal joints directed down- 
wards at right angles to their bases. The same law 
of development holds good as regards the papille 
connected with the inferior spinners of Drassus 
cupreus and Drassus sericeus ; and though their num- 
ber is not uniformly the same even in adults of 
either of these or the preceding species, yet the two 
minute ones belonging to each mammula are present 
invariably. 
One of the most striking peculiarities in the struc- 
ture of the Ciniflonide is the possession of a fourth 
pair of spinners. These spinners are shorter and 
further removed from the anus than the rest, being 
situated at the base of the inferior intermediate pair, 
by which they are almost concealed when in a state 
