xlvi INTRODUCTION. 



inverted, can assist the laden bee to fly in a direct line 

 to its hive, perhaps miles distant. From the convex 

 figure of the compound eye, again, different images 

 must occur side by side. Can the insect be conscious 

 only of those on which its attention is directed ? Has 

 it some power of abstraction and of concentration upon 

 a select group of images ? 



Notwithstanding the labours of J. Miiller, Plateau, 

 Forel, Grenadier, Claparide, Newport, Hickson, and 

 other competent anatomists, the conclusions arrived at 

 are conflicting, and they show that a revision of the 

 subject is much needed. {Vide Sir John Lubbock's 

 interesting remarks, on this and kindred subjects, in 

 ' The Senses of Animals,' Int. Nat. Series, 1888, p. 163 

 ct seq.) 



The Antennas. Fuhler. 



These organs are inconspicuous, and remarkably 

 small in relation to the size of the insects. Their 

 outward presence is often only to be noted by the fine 

 compounded bristles which form their terminal joints. 



The antennae never equal the length of the body, 

 and sometimes they do not equal the breadth of the 

 thorax. They may be inserted below the eyes, or 

 between them, or on the gulffi or cheeks. They are 

 compounded of two short robust basal joints, followed 

 by setae having four, five, or many more articulations, 

 which gradually taper to a point. The exact number 

 of these articulations is not easily made out. Latreille 

 counted only six ; whilst Curtis, West wood, and others 

 make out seven in all. The basal joints are in com- 

 munication with a minute bulb, from which the afore- 

 said bristle springs. 



The Delphacidffi are remarkable for the peculiar 

 forms taken by the second basal joints of the antenna). 

 These joints are large, and in some genera they assume 

 different shapes, as globular, quadrilateral, pyrilbrm, 

 or obtuse. 



Much discussion has arisen as to the function of the 



