U4 MUCOUS 3IEMBRANES. 



elements. It is impossible, even with the best injecting fluids, to 

 fill the lymph-path of the infiltrated gland; indeed injection 

 serves to show the stage at which the process has arrived. Here 

 too, the law which regulates all other progressive changes in the 

 lymphatic glands (scrofulosis, cancer, &c.) is found to hold good, 

 viz. that the swelling should begin at the periphery of the gland, 

 in those parts of it which are nearest the seat of primary disease 

 from which the infecting lymph is drawni, spreading gradually 

 from thence to the entire parenchyma. The degenerative 

 changes follow the same order. These almost always consist of 

 a ^' colliquative softening," with complete fatty degeneration of 

 all the " typhous " cells. Inasmuch, however, as all the lymph- 

 corpuscles and connective- tissue corpuscles, i.e. nearly all the 

 normal corpuscular elements of the gland, have been converted 

 into " typhous " matter, we may readily understand how it 

 comes that hardly anything is left beyond the capsule and the 

 blood-vessels. The uttermost limits of collapse are reached; the 

 antecedent congestion has already given rise to distinct extra- 

 vasations with subsequent pigmentation in the capsule, so that 

 a slaty discoloration figures among the characteristic features of 

 the shrunken ^^ typhous'* gland. 



The occurrence of cheesy necrosis at one or more points of 

 a mesenteric gland in abdominal typhus, must be regarded as a 

 rare phenomenon. Virclww has repeatedly called attention to its 

 possibility. The cheesy slough is then detached by a suppurative 

 inflammation, and a minute abscess results. This may burst 

 into the peritoneal cavity ; hence the risk of peritonitis ; on the 

 other hand, the pus may become inspissated, and finally cal- 

 careous. The earthy nodule is invested with a capsule of 

 connective tissue, like any other foreign body, and the process is 

 at an end. 



§ 382. All the remaining forms of sweUing, productive ac- 

 tivity, ifcc, which are associated with the ^^ typhous" process, are 

 found, upon analysis, to consist of the same series of progress! ^'e 

 and retroojressive chano-es. We know least about the fine 

 anatomy of the splenic enlargement ; the relative proportion of 

 congestion to morbid growth, has not yet been ascertained for tlie 

 different stages of the disease. True medullary infiltratIo]i lias 

 been detected here and there in the Malpighian corpuscles. The 

 ^'typhous'' deposits which are occasionally met with in the 



