Tachardiince. 40 5 



which opens close to the apex, and associated with it are numerous 

 minute glandular bodies communicating with the channel by- 

 thread-like ducts (see PI. CLXXII.y?^. 17). The function of this 

 organ is a puzzle. That it Jias some special function is evident 

 from its structure and from the presence of the associated glands. 

 Its point is not sharp enough to allow of its employment as a 

 sting ; nor is there any indication of the special muscles that would 

 be necessary for its efficacy in such a capacity. Moreover its 

 position — boxed up within the hard resinous cell — would seem to 

 preclude any such use. Its absence in all but the adult stage might 

 suggest some association with the sexual functions, but it is difficult 

 to conceive why this particular genus should have acquired such a 

 peculiar accessory sexual organ. 



The caudal extension probably comprises almost the whole of 

 the abdominal segments, the bulk of the body representing the 

 thoracic area. (It should be recognised that, in the Coccidce, the 

 ovaries are not confined to the abdominal area, but extend upwards 

 throughout the cavity of the body.) The number of visible 

 segments varies, but not more than two or three can usually be 

 distinguished. In some species this area is soft and flexible ; in 

 others the terminal segments m.aybemoreor less densely chitinous. 

 The extremity is truncate, and is surrounded by a laciniate fringe 

 enclosing a circular space in the centre of which is the anal orifice, 

 encircled by ten stout setae. The setiferous anal ring is broad, and 

 is composed of six distinct plates which may become confluent in 

 the adult insect. 



With insects that exude such a copious and dense secretion, one 

 might expect to find definite areas of specialised glandular pores for 

 the purpose. But no such glands have been demonstrated. The 

 only pores that are noticeable are upon areas where wax is deposited, 

 and must be regarded as of a ceriferous nature. A series of such 

 ceriferous pores are to be found surrounding the base of the caudal 

 extension and upon its apex, around the spiracles, and on the 

 extremities of the stigmatic processes. Additional groups occur, in 

 some species, at intervals along the lateral areas. The lac appears 

 to be exuded from the general surface of the body. A study of the 

 deposition of the lac, throughout the various stages of the insects, 

 supports this supposition. 



The adult male may be either apterous or alate, both forms 

 usually occurring in the same species. The antennae are normally 

 ten-jointed, the terminal joint tapering to a point and bearing one 

 or more knobbed hairs at its apex. In the apterous form the 



