THE BUMBLEBEE. 65 



Study the mouth parts, observing another modification 

 and arrangement of them, as follows : 



1. A short, firm labrum. 



2. A pair of strong, horny, biting mandibles. 



3. A proboscis (or sucking organ), bent backward at 

 the middle, and resting against the lower surface of the 

 head and thorax when not in use, and composed of 



(a) A long, hairy, tubular ligula (or central piece) of 

 the labium (centrally). 



(6) Two margined blades of the maxilla (above). 



(<?) Two thin, narrow, elongated labial palpi (below). 

 Separate, and examine these parts with a lens. Draw. 



II. Wings and Legs. Compare fore and hind wings 

 in form, size, and position. 



Draw the fore wing forward by its costal margin, and 

 observe that the hind one moves with it. Find the little 

 hooks (Jiamuli) which hold the two together, securing their 

 unity of action. 



Find coxa, trochanter, femur, tibia, and tarsus in one 

 leg of each pair. How many segments in the tarsus ? 

 Which segment of the tarsus is largest? On which seg- 

 ment of the hindmost legs are the pollen baskets ? Ob- 

 serve with a lens the surfaces to which the pollen masses 

 adhere, and the means by which they are protected in 

 position. Make a detailed drawing of a hind leg. 



III. Thorax and Abdomen. Study the attachments of 

 both wings and legs of the hindmost pair, to ascertain 

 the posterior boundary of the thorax and the beginning 

 of the abdomen. Scrape off the hairs from the top of 

 the thorax, and observe that the metathorax is a narrow 

 segment (antero-posteriorly) ; and a wider segment with- 

 out appendages, the first abdominal segment, is solidly 

 welded to it. The second segment of the abdomen is but 

 a short and narrow stalk-like ring, attaching the ovate 

 hinder portion of the abdomen. Note how the abdominal 



NEED. ZOOL. 5 



