96 THE COCCIDAE 



female. The following quotation from Tepper shows how easily 

 it is for one to be misled by appearances and how unwise it is tc 

 base statements regarding anatomical structures in this family on 

 other than prepared specimens. "Mr. Maskell placed the species 

 (immanis Maskell) in the genus Coelostoma 'on account of the 

 absence of the rostrum' (op. cit. p. 51) and says 'there is no doubt 

 of its being a monophlebid, ' for both Monophlebus crawfordi and 

 Coelostoma australe are known to possess a rostrum (sucking 

 tube) of great length, which during life is deeply buried in the 

 tissues of the bark of the twigs on which the insect is located, 

 when, however, the organ is withdrawn it is at the same time 

 retracted into the body; its extreme slenderness and the minute- 

 ness of the otherwise unmarked orifice rendering it next to 

 impossible to detect its presence. Mr. A. Zietz informs me that 

 he has frequently detached living Monophlebi from the bark and 

 seen their rostrum retracted, and I have noticed in the present 

 instance that the living insect (Coelostoma) had its body closely 

 and immovably fixed to the twig by its rostrum, but later, when 

 dead, had its forepart raised and the rostrum completely retracted. 

 The absence of a rostrum, as a distinction, will, therefore, have to be 

 omitted in future." It is true that living Icerya purchasii are 

 able to conceal the rostrum under folds of the ventral aspect of the 

 head and thorax when removed from the host-plant, but an 

 examination of a specimen clarified in caustic potash will show 

 that anatomically it is impossible for the insect to retract its 

 mouth-parts and the only absolutely sure method of determining 

 whether the mouth-parts are present or absent in a given species 

 or specimen is the study of a properly prepared specimen. 



The adult female is triangular in outline as viewed from above. 

 The cuticle of the body contains circular areas with minute central 

 projections, these will probably prove to be cerores. The 

 cephalic end is pointed and the long tapering antennae of ten 

 or eleven segments are articulated one on each side near the 

 cephalic end of the pointed portion. The caudal end is broad and 

 greatly swollen. The insect as viewed from either side is pointed 

 at the cephalic end and gradually swollen until it reaches its 

 greatest expansion at the caudal end. There is a distinct rim or 

 margin which extends around the pointed cephalic end and along 

 the middle of each lateral aspect to the large transverse truncated 

 caudal end, where the rim is interrupted by the transverse slit 

 leading into the marsupium. The legs are long and slender and 



