OBSERVATIONS ON SCALE-INSECTS (COCCIDAE) — III. 347 



S. Nigeria : Calabar Botanical Gardens, on a hard-wooded scrub, 15.iv.08 {Dr. 

 Slater Jackson). 



This is altogether a very remarkable species, bearing a striking superficial resem- 

 blance to an immature example of a Monophlebid of the genus LojjJiococcus. The 

 crenulated pseudo-margin is however suggestive of certain species of Cteiwchiton ; 

 but it is certainly not congeneric with the latter, and is, I feel, correctly placed in 

 Platysaissetia. 



Akermes andersoni, sp. nov. 



Female, adult. Completely covered with a rather dense, dusky-white, mealy 

 secretion, which also spreads over the surrounding portions of the food-plant, giving 

 the infested leaves an almost uniform mealy appearance. Colour, on the removal 

 of the secretion, rich dark piceous or very dark castaneous, shining ; younger examples 

 varying from reddish brown to dusky buff. Form irregularly oval, asymmetrical, 

 and more or less narrowed in front ; sometimes broadly ovate or subcircular. Flat 

 or very low convex with a faint median keel in the abdominal region ; sides well 

 within the margin, with a series of widely separated truncate tubercles ; these struc- 

 tures vary in number and are often also asymmetrical. Derm densely chitinised, 

 more especially so towards the margins, where innumerable minute, translucent, 

 poreless " cells " are present. 



Female, young adult, (fig. 3, a). In this stage all the structural details are clearly 

 demonstrated ; they do not differ from those of the older examples. Antennae 

 (fig. 3, b) rudimentary ; articulations somewhat irregular and not very clearly defined, 

 five segments being traceable in some individuals ; 1st segment with a few minute 

 hairs ; the terminal one with five to six stout spinose hairs ; length, inclusive of 

 hairs, about equal to the length of the anal lobes. Front pair of legs (fig. 3, c) 

 represented by extremely minute tubercular projections, each furnished with a 

 minute spine— the rudiments of a claw ; these structures measure about one-third 

 the total length of the stigmata. Anal cleft short but well defined. Anal lobes 

 roughly triangular, inner edge longest, straight ; base shortest ; beneath each is a 

 well defined sclerite. Anal ring with eight hairs. Derm immediately above the anal 

 orifice with a series of circular pores and usually four minute spines. Stigmatic 

 clefts (fig. 3, d) generally quite minute, but occasionally there is a great indentation 

 of the margin in this region (? due to arrested development by prominent bodies of 

 the food-plant) ; stigmatic spines (fig. 3, d) three, all very small, the central one 

 the longest. Margin with a complete fringe of very long and relatively stout hairs, 

 and just within them is a widely separated series of minute hairs. The " trimcate 

 tubercles," as seen on the dorsum of the dried specimens, when examined in optical 

 section, show that the ends are composed of numerous circular or ovate pores. In 

 addition to the large compound pores (fig, 3, e) there axe also a few much smaller 

 ones, but their number and arrangement varies in different individuals and they are 

 moreover asymmetrical. Stigmata (fig. 3, /) somewhat trumpet-shaped in some 

 individuals, in others, especially when seen in profile, with a trifoliate flange and 

 a central spheroid process. 



Length, 2 '5-3 mm. ; width, 2-2-2 mm. 



