56 STUDIES OF ANIMAL TYPES 



is found all over the body ? Were the same structures found 

 on the body of the locust? 



Note the two large compound eyes. With a camel's hair 

 brush, carefully remove the scales from the head. Are 

 there any simple eyes? There is no movable flaplike 

 labrum as in the locust. The labrum is small, narrow, and 

 runs transversely across the head. It bears at each end a 

 tuft of fine hairs. Note that there are no mandibles. Note 

 that there is a long proboscis coiled up beneath the " chin." 

 This is made up of the two maxillce, grooved on the inner 

 sides and joined together to form a tube. If the specimen 

 is fresh, the tube may be uncoiled. If it is dry or has been 

 in alcohol, soak the head in warm w T ater until it is soft. 

 The under lip, or labium, is also immovable and forms the 

 under side of the head. Note the two hairy projections 

 pointing upward in front of the head. These come from 

 the labium and are the labial palpi. Compare the antennae 

 with those of the locust. Are they segmented? What is 

 the shape of the antennae at the ends ? This shape is char- 

 acteristic of the butterflies. 



Make a drawing of a side view of the head showing as 

 many of the above points as possible. 



How many wings has the butterfly ? How do they differ 

 from those of the locust? Are they folded at any time? 

 How are they held when the insect is at rest? To deter- 

 mine this, living specimens must be observed in the field. 

 Brush off some of the scales and mount them in alcohol. 

 Examine with the low-power objective and note the 

 shape. Note that the scales differ considerably in size 

 and shape. All gradations may be found from hairs to 

 flat scales. In fact, the scales are modified hairs. Note 

 the longitudinal ridges, or strice. Note the small pro- 



