The Coccidae of South Africa. 
93 
5. Tylococcus chkysocomae sp. n. 
(Plate XVI., Fig. 5. Plate XVIII., Figs. 12-12/.) 
Ovisac (Fig. 5) : White, dense, elongate oval, may reach 5 mm. long 
and 2 mm. in diameter. The ovisacs may be single or clustered. The 
adult 2 is found at one extremity of the ovisac and often appears as 
though partly enclosed owing to the median dorsal keel of white 
secretion. 
Ova : Small, broadly oval, pale olivaceous yellow in colour. 
Larva (mounted from dry material) : Elongate, 0*4 mm. long. Antennae 
of 6 segments, 6 being longest, as long as 3 + 4 + 5 (Fig. 12e). Anal ring 
with six bristles. Caudal lobes very prominent, each bearing one long 
seta and two comparatively long stout spines (Fig. 12/). 
: Not observed. 
Adult $ : Dark olivaceous at time of oviposition, becoming dark 
brown when ovisac is complete. Margins with a fringe of delicate 
filaments, and dorsum with a median keel of white secretion. 
When cleared, stained, and mounted, the adult $ is 2 mm. to 2-5 mm. 
long. Around the margins of the body there is a series of 34 large rounded 
tubercles usually bearing 3 to 8 stout conical spines. In addition to these 
there are other series in which the tubercles are small or obsolete, their 
position being indicated by one or more stout spines. The median dorsal 
series of insolitus is represented, as a rule, by two single spines, separated 
slightly, on the median line, entirely without tubercles. The subdorsal 
series of insolitus is also represented by 1 to 3 spines, with tubercles 
either very small or entirely absent. 
The posterior pair of marginal tubercles take the place of the caudal 
lobes of Pseiidococcus. In addition to stout conical spines, of which there 
are usually 3 to 5, these tubercles bear the caudal setae which are about 
equal in length to those of the anal ring, i.e. about 90 fi long (Fig. 12b). 
The eyes are prominent, roundly conical, with the apical portion 
transparent. Mentum about 132 jj, long. 
The derrais is characterized by numerous large and small gland-pores. 
The large form are disc-like, with very thick rings and small circular 
pores. These are most commonly distributed across the middle of the 
segments. 
The antennae are remarkable in that there are forms with 7 joints, 
others with 8 joints, and a third class with 7 and 8 segmented forms in 
the same insect. The three classes are represented by adult 2 2 with 
completed ovisacs. The measurements, however, are comparatively 
constant, the 7-jointed form ranging : — (1) 34-44 fx ; (2) 51-54 jj. ; (3) 
57-68 ; (4) 44-58 ^ ; (5) 35-40 /x ; (6) 34 ;x ; (7) 88-102 ^ (Fig. 12). 
