Maskell. — On Coccidte. 381 



ledge of the earlier states available I think the fact should be 

 mentioned ; and for this reason I have nearly always (except 

 in the Diasjjidina) inserted the words "Larva unknown" or 

 " Second stage unknown." 



It has occurred to me that a type-series of figures may not 

 be useless as a guide to the study of Coccid larvse, and two 

 plates containing such figures are therefore attached to this 

 paper, showing the abdominal extremities, the antennae, and 

 the feet of the eight principal sections into which the family 

 is divided (Plates XVI., XVII.). I have purposely drawn 

 these figures so as to include as far as possible the most 

 imDortant characters, without special regard to any particular 

 species or even genus, though the variations in the four last 

 groups have necessitated a double arrangement of the ab- 

 dominal extremities. It will be seen, however, that in these 

 double figures the differences shown are by no means funda- 

 mental : thus, for example, in the MonoiMehus section of the 

 MoiiojyhlebincB the difference from Icerya is merely in the 

 number of the setae, the principal character being identical 

 in both — namely, the springing of the setas from the last 

 segment without any tubercles or lobes. As regards the 

 feet, the general similarity in all the groups is apparent ; and 

 the point is to be noted that in every case the tibia is shorter 

 than the tarsus. Morphologically, the antennae also are 

 similar throughout, having always six joints, the aberrant 

 antenna of Tachardia melaleucce really emphasizing the rule. 

 I have given a figure of this antenna (Plate XVII., fig. 4rf), 

 partly on this account and partly to show its approach to the 

 type-form of the Diasjndivce. 



Lest, however, I should be thought to mean that any of 

 the types here shown is to be taken as so definitely fixed as 

 to be rigid, I venture to repeat a passage in my paper of 1890 

 (Trans. N.Z. Inst., vol. xxiii., p. 32) : " Whatever may be the 

 rule amongst other orders and famihes of insects, Coccids pre- 

 sent this difficulty to students : that one must be prepared at 

 any time to find very distinct departures from generic, or even 

 group, types, and to consider any character whatsoever as 

 elastic and variable." Tachardia melaleucce will again furnish 

 an example of this, as the abdominal extremity of the larva 

 is as aberrant as its antenna. 



Note here, with regard to the foot, that in the Monophle- 

 hincR there is only one digitule on the claw. Note also that 

 the appearance shown in Plate XVI., fig. 26, where slight 

 pressure has caused the anal ring to protrude some distance 

 from the terminal cleft, is not infrequent in mounted speci- 

 mens of Lecanid larvae, although by no means constant. 

 Signoret, in his " Essai," gives a similar figure in Philii^pia 

 olece, a Lecanid. Note, finally, that in my Plates I have 



