nto bundles and form rope-like
bands, as in the ligaments of joints and the tendons of muscles. On
boiling, this tissue yields gelatine. In general, where white fibrous
tissue abounds, structures are held together, and there is flexibility,
but little or no distensibility.

[Illustration: Fig. 6.--White Fibrous Tissue. (Highly magnified.)]

21. Yellow Elastic Tissue. The fibers of yellow elastic tissue
are much stronger and coarser than those of the white. They are yellowish,
tend to curl up at the ends, and are highly elastic. It is these fibers
which give elasticity to the skin and to the coats of the arteries. The
typical form of this tissue occurs in the ligaments which bind the
vertebrae together (Fig. 26), in the true vocal cords, and in certain
ligaments of the larynx. In the skin and fasciae, the yellow elastic is
found mixed with white fibrous and areolar tissues. It does not yield
gelatine on boiling, and the cells are, if any, few.

[Illustration: Fig. 7.--Yellow Elastic Tissue. (Highly magnified.)]

22. Areolar or Cellular Tissue. This consists of bundles of delicate
fibers interlacing and crossing one another, forming irregular spaces or
meshes. These little spaces, in health, are filled with fluid that has
oozed out of the blood-vessels. The areolar tissue forms a protective
covering for the tissues of delicate and important organs.

23. Adipose or Fatty Tissue. In almost every part of the body the
ordinary areolar tissue contains a variable quantity of adipose or
fatty tissue. Examined by the microscope, the fat cells consist of a
number of minute sacs of exceedingly delicate, structureless membrane
filled with oil. This is liquid in life, but becomes solidified after
death. This tissue is plentiful beneath the skin, in the abdominal cavity,
on the surface of the heart, around the kidneys, in the marrow of bones,
and elsewhere. Fat serves as a soft packing material. Being a poor
conductor, it retains the heat, and furnishes a store rich in carbon and
hydrogen for use in the body.

24. Adenoid or Retiform Tissue. This is a variety of connective
tissue found in the tonsils, spleen, lymphatic glands, and allied
structures. It consists of a very fine network of cells of various sizes.
The tissue combining them is known as adenoid or gland-like tissue.

[Illustration: Fig. 8.--Fibro-Cartilage Fibers. (Showing network
surrounded cartilage cells.)]

25. Cartilage. Cartilage, or gristle, is a tough but hi