522 Professor R. Newstead on Homoptera 
Stictococcus sjdstedti, Newstead, Journ. Econ. Biol., vol. ii, 
p. 149 (1908). 
This remarkable Coccid is one of the recognised cocoa 
pests of Western Africa. I have already noted * that this 
species and also S. formicarius, Newst., are preyed upon 
by Lepidopterous larvae, though I was unable to determine 
the group to which the latter belonged. 
In examining the material kindly furnished by Prof. 
E. B. Poulton, I have discovered that the larvae of 
S. sjdstedti are undoubtedly dimorphic. In one of the 
females there is one embryo larva of each sex still remaining 
in the body of the parent, so that there can be no possible 
doubt as to the authenticity of this record. This dis- 
covery clears up the marked discrepancies existing between 
the descriptions of the larvae given by Prof. Cockerell 
and myself, respectively. Now that I have the larvae of 
both sexes before me it is perfectly obvious that the larva 
described by myself was that of the male, while that 
described by Cockerell was undoubtedly that of the female. 
The differential characters may be briefly summarised as 
follows :— 
Male larva. Female larva. 
Mouth : .  ? Obsolete. Normal. 
Anal orifice . Anal. In the middle of the back. 
Marginal spines Of great Jength. Short, of two types: one broad 
and dactyliform, the other 
curved and serrated. 
The examples in question are so much distorted in the 
preparation that it is impossible to add any further particu- 
lars at this juncture; neither can I be quite certain as to 
whether there is a mentum present in the male larva or 
not, but as there is no trace of the buccal filaments I 
assume that the mouth is obsolete, as is certainly the case 
with the male larva of S. dimorphus,t Newst. Thus we 
now have two well-marked instances of sexual dimorphism 
in the larvae of the Coccidae, both belonging to the genus 
Stictococcus : characters which are not only very remark- 
able but quite unique and unprecedented in this group 
of insects. 
See also pp. 447-50, 460, 462, 491-2. 
* “ Journ. Econ. Biol.,” vol. v, p. 22. 
+ * Bull. Ent. Res.,” vol. i, p. 63, fig. 2 (1910). 
