66 INSECTS NOXIOUS TO AGKICULTUKE. 



The antennae of the adult female have six or seven joints. 

 It is often very difficult to determine the number, as the third 

 joint exhibits frequently a shallow circular depression or ring 

 which may easily be mistaken for a division. 



During gestation the female, which at first fills the test, 

 shrivels up at one end into a shapeless mass requiring macera- 

 tion in potash to restore the original form for examination. 

 The test thus becomes almost filled with eggs. 



The presence of the fringe, which is noticeable in every 

 species of this genus at some time or other, distinguishes it from 

 Ceroplastes and Vinsonia. In Ctenochiton viridis the test is not 

 to be made out in the adult stage but is clearly visible in the 

 second stage of the female, and it is present, with the charac- 

 teristic fringe, for the male. 



31. CTENOCHITON DEPRESSUS, Maskell. 



N.Z. Trans., Vol. XVI., 1883, p. 132. 



(Plate VII., Fig. 2.) 



Test of adult female flat, nearly circular, thin, waxy, greyish- 

 coloured ; fringe inconspicuous or sometimes absent. No per- 

 forations or rows of air-cells. Diameter, about i^in. 



The fringe is more conspicuous in the test of the second 

 stage. 



Test of male elongated, narrow, flat beneath, slightly convex 

 above, white, glassy, thin and brittle, with a conspicuous fringe 

 of which the segments are truncate-triangular. The test is 

 divided into tessellations, the median row of which is quadran- 

 gular, with two series of pentagonal divisions between it and the 

 fringe. Near the abdominal extremity a transverse narrow slit 

 cuts the test in two, leaving a small segment at the extreme end 

 apparently separate. Length of the test about j^in. 



Adult female filling the test, but shrivelling after gestation ; 

 colour brownish or grey. Antennae of six joints, the third being 

 the longest, and, as is commonly the case in the genus, often 

 appearing like two. On the last joint a few long hairs. Foot 

 normal ; the upper digitules are fine hairs, the lower pair only a 

 little broader. Anal ring and lobes normal. 



In the second stage the usual wavy edge is conspicuous ; the 

 test is thin, glassy, with normal fringe. Antennas and feet 

 normal. The insect is somewhat thick, with yellowish colour. 



