SUGGESTIONS FOR LABORATORY WORK 591 



flexion; (3) abduction, drawing the leg outward from the body; 

 (4) adduction, the opposite of abduction; (5) rotation, twisting at 

 the joint as in placing ankle on knee. 



In addition to these elementary joint movements, the hip joint 

 permits various combination movements, as flexion with abduc- 

 tion. Note these. 



Knee Joint. Observe the surfaces on femur and tibia which come 

 together at the knee. Analyze the possible movements of this 

 joint. 



Ankle Joint. Observe the possible movements of this joint. 



MUSCLES 



For dissection studies the cat is the most available mammal.* 

 Detailed descriptions are given in "The Anatomy of the Cat" by 

 Reighard and Jennings. For purposes of illustration directions 

 for a single region are included here. 



Dissection of Hind Leg of Cat. Directions for dissection. 

 Muscles are inclosed in and bound together by sheets of connective 

 tissue, which make up the fascia. To dissect out a muscle cut or 

 tear through the fascia which joins it to its neighboring muscles 

 until the desired muscle can be lifted clear except for the attach- 

 ments at its ends. Do not cut attachments until you have finished 

 the study of the muscle. 



The attachment of the muscle nearer the trunk is called the 

 origin; the attachment further from the trunk is the insertion. 



In dissecting the hind leg of the cat, consider it as made up of 

 four regions: pelvis, thigh, shank, and foot. The muscles are to be 

 dissected in order as directed below. As each is cleared from its 

 surrounding muscles the region in which it has its origin is to be 

 determined, also the region of its insertion. 



Muscles are grouped functionally, according to the joint-motions 

 they produce, as flexors, extensors, abductors, adductors, and ro- 

 tators, f Determine for each muscle the region it moves and the 

 motion it produces. 



On the outside of the thigh is the biceps femoris. Abductor of 



* If there is a pork-packing establishment in the vicinity embryo pigs can 

 usually be obtained in ample numbers. These make exceedingly satisfactory 

 dissection material, especially for elementary classes. 



t Elevators, depressors, and sphincters occur in the Body but not in the leg. 



