74 



ELEMENTARY LESSONS ON INSECTS 



hand compare part by part with the insects of the other 

 orders studied, noting especially: 



1. The broad, stout body, closely overlaid behind by the 

 overlapping wings. 



2. The head tapering forward to the beak. 

 In the head note: 



1. The jointed beak, directed back- 

 ward between the fore legs when 

 not in use. Its composition may 

 best be studied in microscopic 

 mounts of heads of some of the 

 small Homoptera. The usual 

 mouthparts are present but in 

 greatly altered form. The jointed 

 sheath enclosing the other parts is 

 the modified labium. Two pairs of 

 channelled stylets, laid close to- 

 gether to form the sucking tube, 

 represent the maxillae and man- 

 dibles, and a small lancet-like 

 pointed labrum overlies their bases 

 in front. 



2. The prominent few-jointed an- 

 tennae. 



Fio.28.-The cicada and its nymph. j n ^ thorax note . 



1. The angular form of the prothorax. 



2. The openings of the stink glands, a pair of minute 

 pores on the sides of the mesothorax beneath, close to 



