166 DIASPIS ZAMT^. 



filaments short, not reaching the posterior spiracles. 

 Parastigmatic glands, present at each of the four 

 spiracles, number from 3 to 6, the posterior groups 

 having the less number. Spiracles shaped somewhat 

 like those of Aspidiotus nerii. Dermis, except the 

 cephalic area, thickly set with short tubular spinnerets, 

 which are most numerous at the margins of the free 

 abdominal segments, and form a very characteristic 

 feature under the microscope. Pygidium (PI. XVII, 

 fig. 1) short and broad, has the anal opening a little 

 anterior to the centre. Circumgenital glands absent. 

 There are a number of very short, broad, dorsal, 

 tubular spinnerets somewhat irregularly placed, except 

 at the extreme margin, where they are usually arranged 

 in 3 4 pairs, and there is one placed in the centre 

 just within the median plates. The characteristic 

 features of the margin (PI. XVIII, fig. 4) are the 

 long, stout, bifurcated plates, of which there are two 

 short ones between the median lobes, and one anterior 

 to the latter and the first and second lobes ; these 

 three are longest and most constant in character ; 

 beyond them are seven to eight others, more or 

 less spine-like, and suddenly dilated towards the base. 

 Median lobes, divergent, are widely separated at the 

 base, and finely and widely serrate on the inner 

 lateral free margin; the second and third pairs are 

 divided ; each of the posterior lobules being much the 

 largest, are usually broadly rounded, and have the 

 margins entire or faintly notched, while the anterior 

 lobules are either of a similar character or, as is 

 often the case, pointed and like broad angular 

 spines. The fourth lobe is either rounded or angular, 

 and is sometimes wanting ; there are three to four 

 projecting pores, the first and second immediately 

 anterior to the second and third bifurcated spines. 

 The others are beyond them, and usually less pro- 

 nounced. 



Male unknown in any stage. 



Larva, short ovate, has six subequal joints to the 



