44 ELEMENTARY BIOLOGY. [CHAP. 



y. The falciform ligament (suspensory ligament of 

 the liver). Cf. supra. If the section has passed 

 through the anterior border of the liver, this will 

 also be seen to pass between its outer edges and 

 the body-wall. 



j. The sub-cutaneous lymph-spaces ; seen (in this and 

 the preceding section) as a series of four spacious 

 chambers, lying between the body-wall and in- 

 tegument, and separated from each other by mem- 

 branous partitions. 



k. The anterior abdominal vein; this will probably be 

 seen, enclosed within the folds of the mesentery 

 immediately below the liver. 



3 Across the head ; to pass through the mouth-cavity 

 and eyes. 



a. Note the absence of body-cavity and the relatively 

 great size of the neural canal and central nervous 

 system (brain). 



b. The mouth cavity; spacious, and enclosed on all 

 sides in a soft mucous membrane. 



c. The tongue; a median up-growth of the floor of the 

 mouth, supported at its base by a cartilaginous 

 plate, the hyoid. 



d. The eyes ; spherical sacs with firmly resistant cap- 

 sules, closely applied to the outer integument. 

 Note, in connection with them, 



a. The eye-muscles; passing backwards and down- 

 wards, between the eye-ball and cranial wall. 



ft. The eye-lids ; folds of integument above and 

 below the eyes, continuous at their bases with 

 a delicate fold of skin (conjunctiva) which invests 



