THE COCCI DAE OF SOUTH AFRICA.— III. 209 



The pygidium is remarkable for its even, wavy or crenulate margin. There are 

 two pairs of low lobes and very few plates in mature specimens, but before the 

 integument has become densely chitinised the pygidium is exceptionally beautiful. 

 There are then two pairs of well-defined lobes and indications of at least one other 

 pair of rudimentary lobes, but the whole margin is so deeply crenulate and regularly 

 supplied with gland openings that it is difficult to describe precisely otherwise than 

 as lobulate. L, large, broadly rounded ; L., about half as large, with the outer edge 

 notched. The dorsal embossed area in this stage is faintly but distinctly noticeable, 

 the thin areas reminding one of fat globules as seen under the microscope. There 

 are seven or eight pairs of long spines at intervals from the second pair of lobes to the 

 base of the pygidium. The ventral surface is longitudinally rugose and, near the 

 margin, there are numerous gland openings with their long axes perpendicular to the 

 margin. Of dorsal glands there are five well-defined series ; the first, which is short 

 and comprises about 6-7 glands, arises from the inside of the rudimentary L 3 ; the 

 second, of 2-5 glands, reaches to the level of the vulva ; the third, fourth and fifth 

 do not appear to reach the margin and consist of about 20, 10 and 5 glands respectively. 

 Pygidium of mature, fully chitinised specimen, as figured (fig. 122). ©ifcumgenital 

 glands 0. 



Habitat : On Acacia horrida, Willd., Stellenbosch, OP. ; collected by T. F. 

 Dreyer, 23rd May 1906. On Acacia horrida, Willd., associated with Asterole- 

 canium 'from S.W. Africa, 1903 (Cape No. 1,137). 



Collection Nos. : 218, 218a. 



108. Pseudaonidia trilobitiformis (Green) (Plate xii, fig. 126). 



Aspidiotus trilobitiformis, Green, Ind. Mus. Notes, iv, pt. 1, p. 4, 1896 ; id., Cocc. 

 Ceylon, i, p. 41, 1898 ; d'Emmerez, Pr. Soc. Amic. Scien. p. 26, 1899. 



Scale of adult 2 large (may reach 4 mm. in diameter), flat, sometimes circular, 

 but more often with one side flattened against a vein of a leaf. The colour is usually 

 brown or reddish brown, but in old exposed specimens it is commonly more or less 

 bleached. The exuviae are flat and usually yellowish to brownish. The form and 

 colour of this scale are very similar to those of a t) r pical Selenaspidus species. 



" Adult female clear brown ; surface hard and horny, polished, with' numerous 

 delicate transverse striated lines. Form oblong, rounded in front, tapering to a point 

 behind ; dorsal surface flattened ; ventral surface slightly tumid ; segments distinct 

 and strongly defined ; a deep transverse groove on dorsal surface between the 

 prothoracic and mesothoracic segments ; a large irregular depressed space on each 

 side of rostrum, covered with white waxy secretion, marking the position of the 

 parastigmatic glands, of which there is a group consisting of from 12 to 20 orifices 

 in front of each of the anterior stigmata. Pygidium with eight prominent obscurely 

 tricuspid lobes ; mesal pair stoutest, but scarcely as long as second ; others rather 

 slender. Squames deeply fringed ; two in the mesal and first spaces, and three in 

 the second and third spaces between the lobes. Lateral margin of pygidium 

 irregularly serrulate, with two deep notches marking the position of the obliterated 

 second and third abdominal segments. On the dorsal surface is an extensive 

 reticulated tract completely occupying the median area of the pygidium between 

 the base and the anal aperture, the boundaries well defined and constant, the spaces 



(C507) c 



