772 J. P. SIMOKDS 



others. This tendency to the development of adenomas in old age is in 

 harmony with Goodpasture's conception, that as individuals grow old 

 many cellf by dedifferentiation i. e., by the "elimination of structural 

 differences" free themselves of the more rigid demands of functional 

 specificity and become capable of growth. 



Circulatory Disturbances 



Hemorrhage. Hemorrhage into the hypophysis may occur from vari- 

 ous causes. Strauch observed subcapsular hemorrhages in a case of 

 internal hydrocephalus. Simmonds(/) and Schmorl have seen hemorrhage 

 into the hypophysis as a result of trauma. In several cases of fracture 

 of the base of the skull I -have found hemorrhage into the capsule of the 

 hypophysis but not into the substance of the gland itself. Hunter (6) and 

 the author found hemorrhage into the pituitary body in cases of apoplexy. 

 In my case, about one-third of the posterior lobe was densely infiltrated 

 with blood. Hemorrhage into the anterior lobe following thrombosis of a 

 blood vessel of the hypophysis has been described by Merkel and Berb- 

 linger(c). In the posterior lobe of a 60-year-old man who died of hemor- 

 rhagic (lethargic) encephalitis, I found numerous, minute hemorrhages 

 into the substance of the posterior lobe. Hemorrhages into the hypophysis 

 are frequently agonal. Luzzatto and Lubarsch found hematogenous pig- 

 ment, the remains of an old hemorrhage, in the neurohypophysis. Hemor- 

 rhage into tumors of the hypophysis are common ; extensive extravasations 

 of blood into neoplasms having been recorded by Bailey, Eppinger, Eisen- 

 lohr, Anders and Cattell, and Michel. 



Ilyperemia. In the examination of a large series of hypophyses, one 

 is impressed by the very great variation in the amount of blood present in 

 the anterior lobe in different specimens. The blood vessels of the hypoph- 

 ysis are thin-walled and are capable of easy dilatation. Passive hyper- 

 em ia of the hypophysis may be caused by any condition which induces an 

 overfilling of the intracranial veins and sinuses, such as pressure by 

 tumors upon the veins of the neck, valvular disease of the heart, etc. 

 Strauch noted "excessive hyperemia" of the anterior lobe in a 9-year-old 

 girl suffering from hydrocephalus. 



Abramow found hyperemia of the anterior lobe of the hypophysis as a 

 constant change in experimental diphtheria in guinea pigs. In 22 out of 

 62 hypophyses examined by Thorn there was dilatation, and sometimes an 

 increase in the number, of the blood vessels, associated with a variety of 

 pathological lesions in other parts of the body. The most pronounced 

 hyperemia in my series of hypophysis was in one form a man who died 

 from hemorrhagic (lethargic) encephalitis. 



