— 59 ~ 



dorsal and ventral orbits of the eyes. Each gena presents a 

 triangular expanded portion lying between the base of the 

 maxillary proboscis and the caudo-mesal angle of the eye. 



Postgenae. — The postgena; are two important sclerites, 

 constituting the caudal portions of the orbits of the eyes, 

 and also the lateral portions of the caudal aspect of the 

 head. The chief portion of the postgena are the broad sur- 

 faces caudad of the eye. 



On account of the obliteration of certain sutures, a more 

 detailed study of the fixed * parts of the head is not feasible 

 for the elementary student. 



THE MOVABLE PARTS. 



Certain parts of the head plainly movable in the ^ocust 

 and in the beetle are immovable in Anosza, but their 

 homology with the movable parts heretofore studied, and 

 their homologous distinctness from the ' ' fixed parts ' ' of 

 the head, justify reference to these immovable but homol- 

 ogous equivalents of the movable parts of the head in other 

 insects as ' ' movable parts. ' ' 



Antennae. — The rather long, knobbed antenna', have 

 their insertions cephalo-mesad of the dorsal margins of the 

 compound eyes. Note the ringed or jointed structure of 

 the antennae, and the swelling club of the tip. 



Labrum. — Immovably joined to the cephalo- ventral 

 margin of the clypeus is a very narrow, mostly transversal 

 sclerite, the labrum. It bears two, tapering, cephalad-pro- 

 jecting points, t\\e pih'fers, rising from the ends of the trans- 

 verse portion of the sclerite. Each pilifer bears on its mesal 

 margin a row of short, bristly hairs, light brown in color. 

 There is also to be made out a very small, triangular piece 



* For a determinatian of the sclerites of the head of Anosia plexippus, based on a 

 comparative study of various lepidopterous heads, see article by the junior author 

 of these notes entitled "The Sclerites of the Head of Danais archippus Fab.' 

 [=Ansoia plexippus], in Kansas University Quarterly, Vol. II, No. 2, Oct., 1893. 



