406 DR, E. KLEIN. 
propria of the alveoli and the thin connective-tissue lamellz 
separating these latter. 
In Fig. 13 these interalveolar lymph-clefts of a portion of 
a serous gland in the root of the tongue of the rabbit are 
well shown. 
Both the ducts of the mucous and serous glands possess 
their own lymphatics ; they appear as lymph-spaces extending 
along the duct for a longer or shorter distance, and in many 
cases either completely invaginating it, or only partially so, 
as in Figs. 14 and 15. 
48. The relation of the lymphatics to the striped muscle- 
tissue, where it occurs in the mucous membrane itself, e.g. 
in the lip, palate, and tongue, is a very intimate one. 
We have already mentioned the large lymphatic vessels 
present in the connective-tissue septa between the bundles 
of the muscle-tissue ; they are connected into a plexus whose 
vessels run chiefly in a direction parallel to the long axis of 
the bundles. These vessels may be appropriately called the 
interfascicular lymphatics. Just as is the case with the fat- 
tissue, so also here, the ultimate lymphatic radicles are 
lymph-spaces between the individual muscle-fibres. Each 
muscle-fibre of a bundle is surrounded by a lymph-space 
(see Fig. 16.), and this latter is consequently contained 
between the sarcolemma of the muscle-fibre and the con- 
nective tissue separating the individual muscle-fibres, ?.e. 
the endomysium. These lymph-spaces may justly be termed 
the entrafascicular lymph-clefts. The lymphatics, therefore, 
existing in the bundles of the striped muscle-fibres are 
identical with these of the nerve-bundles as described by 
Key and Retzius. 
49. We have finally to mention the existence of continuous 
lymph-spaces in the sheath of the nerve-bundles and the 
capsule of the ganglia, existing in the connective tissue both 
between the lobules of the glands and between the bundles 
of the muscle-fibres in the root of the tongue. These spaces 
correspond to the perineural lymph-spaces described by Key 
and Retzius of the cerebro-spinal nerves in general. 
