378 Devolopiiiciit of tlu' Ijyiii|iltatie Xodos in tlic Pig 



depth botwoen the arteries, thert'hy exteiuliiii;- the sinuses and definitely 

 limiting the lymph cords. Indeed, the true lymph cord of the adult 

 condition now appears for the first time. The diagram shows well the 

 nature of the lymph sinuses consisting of rows of closely packed lymph 

 ducts. The bridges between them are still protoplasmic and slightly 

 wider tlian they appear in the adult nodes. 



The diagram shows the rel-ition of the trabecula? to the capsule and 

 the sinuses. Here for the firsi time there is a definite capsule and it is 

 interesting to note that it is not complete. It extends along the margin 

 of the peripheral sinus but ends abruptly on the right hand side of the 

 section, where the node consists of a plexus of lymph ducts. It will be 

 noticed that there is a definite indentation in the margin of the node 

 where the capsule ceases. At this place the node can increase in size by 

 invading the surrounding tissue. 



The structure of the capsule itself is best studied in good Mallory 

 specimens with the oil immersion lens. For this study it is necessary 

 to note the condition of the surrounding connective tissue. This has 

 been described by Professor "Mall." There is in the first place in tlie 

 surrounding tissue a delicate network of fine but definite anastomosing 

 fibrils. The nuclei of the network are in the nodes, and most of them 

 form part of the characteristic spindle cells. This is the prefibrous 

 tissue of Mall; the fine fiber network is still slightly granular, repre- 

 senting the protoplasmic syncytium of the earlier stages. Most of the 

 definite protoplasm is around the nuclei. Beside this fine fiber network 

 there are large bundles of definite fibers. The fibers of these bundles 

 are several times the width of the fibers of the network, and the bundles 

 themselves are often eight or ten times the diameter of a red blood cell 

 in width. Many of these bundles have several spindle cells clinging to 

 them. The large bundles are found near the border of some gland or 

 muscle, while in the less differentiated areas every transition between 

 the fine network and the coarse bundles can be made out. As Mall has 

 shown, these are the white fiber bundles developing from the prefibrous 

 tissue. The fibers of the bundles are close together and are straight. 

 The capsule of the lympli node is different both from tlie fine network 

 and from the white fibrous bundles. It consists of a dense network of 

 anastomosing fibers. These fibers are larger and sharper than the fine 

 fiber network, but they are much finer than the fiber bundles. They 

 are wavy and closely packed. In other words, they differ from the fine 

 fiber network by being larger, sharper, and more closely packed, and 



* Ibid. 



