yS Mytilaspis. 



MYTILASPIS CITRICOLA, Packard. 



(Plate XX.) 



Aspidiotiis f/7r?V^/^z (Packard). Guide to the Study ^/ /«J^r/j', 2nd edition 



(1870), p. 527. 

 Mytilaspis citricola (Packard). Comstock, U.S. A_^. Report., 1880. 



Female puparium elongate, mussel-shell shaped, usually slightly curved, 

 dilated behind, with a narrow flattened marginal area not very sharply defined 

 ^fiS,- -)• Colour reddish brown or olivaceous brown, paling on the marginal 

 area. The scale is transversely rugose with numerous curved lines of growth. 

 The pellicles occupy rather more than one-third the total length. First pellicle 

 exposed, pale yellowish. Second pellicle reddish ; more or less concealed 

 beneath a layer of secretion, but when separated and cleaned it is seen to have 

 a blunt point on the lateral margin of each of the four basal abdominal 

 segments {fig. 8). Ventral scale well developed, whitish ; completely enclosing 

 the insect {fig. 3) ; without any median division, except near the anterior 

 extremity, where is an opening for the rostral setce ; not extending to the edges 

 of the dorsal scale, but attached at some little distance from the margin ; with a 

 large irregular opening behind, exposing the eggs which are irregularly disposed 

 in the cavity. The surface of the ventral scale is marked and pitted with the 

 impress of the orange rind or leaf upon which it may ha\e been fixed. Length 

 of complete scale 2 to 3 mm. Breadth o-8o to i mm. 



Male puparium {figs. 5 & 6) smaller, narrower, and of more delicate texture ; 

 sides nearly parallel ; pellicle occupying nearly one-third of total length. At 

 about one-fifth from posterior extremity is a distinct transverse paler line where 

 the scale is thinner, acting as a hinge, so that the hinder part of the scale can 

 be raised to allow of the exit of the adult insect. Colour varying from pale 

 olivaceous brown to dark reddish brown, the part behind the hinge usually 

 tinged with purplish brown. Pellicle pale straw colour. \^entral scale incom- 

 plete, represented by a narrow whitish strip on each side attached a little way 

 within the margin and extending backwards as far as the hinged part of the 

 scale. Size about i"5o by o'4o mm. 



Adult female creamy white, terminal segment reddish fulvous. Oblong, 

 narrow in front, widest behind. Abdomen deeply segmented laterally. An- 

 tennae consisting of a small tubercle and two stout curved hairs {fig. 10). A 

 small group of glands round the anterior stigmatic openings. Pygidium {fig, \\) 

 broad, two moderately large median lobes with the free edges crenate and 

 sloping from each side to an obtuse angle, followed closely on each side by a 

 shorter duplex lobe of which the outer lobule is the smaller ; other lobes 

 obsolete. There are three marginal indentations on each side beyond the 

 lobes. Squames tapering, spine-like, one pair between the median lobes, a 

 pair in each space between median and second lobes, and a pair springing 



