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glass. Examine it with a microscope using a low power and 

 reflected, not transmitted, light (i.e., turn the mirror so that 

 the field of the microscope is dark ; and place the micro- 

 scope so that a strong light falls upon the specimen). Make 

 a drawing of the caudal aspect of the labium, and letter the 

 parts. 



Study the distal end of the distal segment of a labial pal- 

 pus with a higher objective. Observe the sense papillae with 

 which it is furnished. Make a drawing of this part. 



Parts of the maxillae. After the removal of the labium 

 it is easy to distinguish the maxillae, of which there is one on 

 each side between the labium and the mandibles. 



Remove a maxilla and mount it in Canada balsam or 

 glycerine, with the caudal aspect uppermost. Examine with 

 a microscope using a low objective, and reflected light. 



Make a drawing of a maxilla, and name the parts, which 

 are as follows : 



Cat-do. The cardo or hinge is the proximal part of the 

 maxilla. It consists of two sclerites ; the first is the larger 

 and is triangular in outline. 



Stipes. The stipes or footstalk is the large, quadrangular 

 sclerite which forms the central part of the maxilla. 



Lacinia. Articulated to the distal end of the stipes is a 

 large sclerite, which tapers distad, is curved, and is termi- 

 nated by strong teeth ; this is known as the lacinia j it is 

 called also the inner lobe. 



Galca. Joined to the side of the stipes near its distal end 

 and projecting laterad of the lacinia is a part consisting of 

 two segments. This is the galea. The distal segment of the 

 galea is large, spoon-shaped, and covers the inner lobe like a 

 hood ; the proximal segment is constricted in the middle so 

 as to resemble slightly a dumb-bell in outline. The galea is 

 also known as the outer lobe, upper lobe, or superior lobe. 



Palpifer. Joined to the lateral border of the stipes and 



