Maskell. — Oih Coccididae. 39 



conditions, and, if so, how the ants and they mutually behave 

 to each other. There appears to be a general consensus of 

 opinion that Aphides are made use of by ants for their honey- 

 dew — or, as frequently stated, employed as "milch-cows:" 

 but this is the first instance that I know of where ants and 

 Coccids dwell together ; and the quantity of honey-dew ex- 

 creted by the Bijjcrsia cannot be very great. It is to be 

 regretted that naturalists so frequently neglect to enter into 

 any detail about their observations. I think I can recall a 

 number of casual remarks and incidental allusions tending to 

 indicate that Coccids of various species furnish food, through 

 their honey-dew, to ants ; but no previous definite statement 

 by any author is known to me. ■■'■ The point, nevertheless, is 

 not without interest. 



SPECIES OF UNCEETAIN POSITION. 



On various species of Casuarina in Australia there occur 

 some Coccids which I cannot at present assign to any known 

 genus, or even to any definite group. Having examined 

 numerous specimens of adults and larvae, I confess myself 

 fairly puzzled. No specimen of a male or of a male pupa has 

 come under my notice ; males might perhaps clear up the 

 difficulty. It will be seen presently that in treating of the 

 Brachyscelid group I draw attention to the presence therein 

 of an excessively prolonged abdominal region : in the insects 

 about to be described this feature does not appear, and they 

 may therefore not be Brachyscelid. The simple, hairless 

 anogenital orifice points to the Monoplilehida : but I am not 

 prepared as yet to place them there. The larvge may be 

 either Dactylopid or Monophlebid : the adults do not agree 

 with any known Dactylopid form. On the whole, probably, 

 the balance will be in favour of their Monophlebid relation- 

 ship ; but then the group will have to be somewhat extended 

 to receive them. 



Sph^eococcus. Gen. Nov. 

 I am not yet prepared to attach definite characters to this 

 genus. 



SphserococcTis casuariiiEe, sp. nov. Plate VIII., figs. 8-20. 



Adult female globular, naked ; the cephalic portion greyish, 

 the abdominal region dark-brown ; there is usually a small 

 quantity of white cotton under the body ; diameter about 



* Whilst this paper is in the press, I find that Mr. J. W. Douglas, in 

 the Entomological Monthly Magazine for September, 1S91, describes an 

 Ortliczia found in ants' nests in Colorado ; but it is not quite clear whether 

 this Ortliczia inhabits ordinarily the nests or was taken there acci- 

 dentally. 



