Maskell. — On CoccididEe. 41 



tion, and the larva just described was one which emerged from 

 the mother. There was consequently no further room for 

 doubt that the two insects are separate and distinct. 



Cylindkococcus. Nov. Gen. 



Insects inhabiting galls which appear to be evidently 

 aborted and misshapen forms of the twigs of the plant, as in 

 each case the teeth or small scales seen at the ordinary joints 

 have become a thickish mass clothing the base or the surface 

 of the gall. In the two species about to be described only the 

 anterior pair of feet are present, the others being represented 

 by merely small dark patches on the epidermis. Anal seg- 

 ment circular, slightly convex, not prolonged in a " tail." 



The galls formed by the two species differ. That of C. 

 casuarince is long and slender, varying from nearly lin. long 

 and l^in. wide at the base to not much more than |-in. long and 

 ■Jgin. wide at the base. The gall is smooth, except for the 

 clothing of small scales round the base. That of C. spiniferus 

 is externally much thicker in proportion to its length. Speci- 

 mens observed vary from fin. long and ^in. wide at the base 

 to nearly lin. long and more than iin. wide. The whole gall 

 is very rough, being covered from base to tip with pointed 

 scales, which are larger than the ordinary scales of the plant. 

 In the interior, however, of this rough gall there appears to be 

 always a central narrow elongated tube in which the insect 

 is found, resembling thus the gall of G. casioarince. 



I am not acquainted with any other genus of Coccids in 

 which the anterior pair of feet only are preserved in the adult 

 female. In the genera Capnlinia, Signoret, and Opisthoscelis, 

 Schrader, the posterior pair are alone visible. Gijlindrococcus 

 is therefore entirely distinct, if only on this account. 



Cylindrococcus casuarin^, sp. nov. Plate IX. 



Insects inhabiting long narrow cylindro-conical galls, which 

 appear to be evidently aborted and misshapen forms of the 

 twigs of the plant, as in each case the small scales seen at 

 the ordinary joints have become a thickish mass clothing 

 the base of the long narrow gall. These galls vary in length 

 and thickness : some are nearly lin. long and |^in. wide near 

 the base ; others not more than ^in., and proportionately 

 slender ; but I have found adults, or remains of adults, in 

 both large and small. The extremity of the gall is somewhat 

 sharply pointed ; the consistence varies, some being rather 

 solid and hard, others appearing more like several strijps 

 pasted together more or less lightly. The interior is always a 

 cylindrical tube ; the exterior is smooth above the basal 

 scales. 



The adult female occupies the lower end of the tube, her 



