92 ELEMENTS OF HISTOLOGY. [Chap. xn. 



120. Lymphatic vessels are developed and newly 

 formed under normal and pathological conditions in 

 precisely the same way as blood-vessels. The accom- 

 panying woodcut (Fig. 56) shows this very well. We 

 have also here to do with the hollowing out of (con- 

 nective tissue) cells and their processes previously 

 solid and protoplasmic. 



CHAPTER XII. 



FOLLICLES OR SIMPLE LYMPH-GLANDS. 



121. UNDER this name we include the blood- 

 glands, or the conglobate gland substance of Hewson, 

 His, and Henle, or the lymph-follicles (Kolliker, 

 Huxley, Luschka). The ground-substance of all 

 lymph-glands, simple as well as compound (see 

 below), is the lymphatic or adenoid tissue, or leuco- 

 cytogenous tissue. Like all other gland-tissue, it k 

 supplied with a rich network of capillaries derived 

 from an afferent artery, and leading into efferent 

 veins. 



122. The elements constituting this tissue are : 



(a) The adenoid reticulum (Fig. 57), a network 

 of fine homogeneous fibrils, with numerous plate-like 

 enlargements. 



(b) Small, transparent, flat, endotheloid cell-plates, 

 each with an oval nucleus. These cell-plates are fixed 

 on the reticulum, of which at first sight they seem 

 to form part. Their oval nucleus especially appears 

 to belong to a nodal point i.e., to one of the 

 enlargements of the reticulum ; but by continued 

 shaking of a section of any lymphatic tissue, the oval 

 nuclei and their cell-plates can be got rid of, so that only 

 the reticulum is left, without any trace of a nucleus. 



