DR. H. WATNEY OR THE MINUTE ANATOMY OF THE THYMUS. 
1069 
the thymus with the lymphatic glands, and said that it contains a network like that of 
the Peyer’s patches. 
Jendrassik (30), 1857, considered that the lobules are solid, for though he noticed 
in some cases a hollow running through the gland, he also found portions removed from 
the rest, in which there was no canal. He thought that the hollows arise by a softening 
process, and agreed with Kolliker (48) that the vessels penetrate the follicile, as he 
noticed large veins in their centre. He concluded that the concentric corpuscles 
compress and obliterate the vessels, and that they are thus concerned in involution. 
He observed extravasations of blood, of which some were recent and some degenerated ; 
and that degenerated blood corpuscles are found in the concentric corpuscles. 
Berlin (31), 1857, doubted if the concentric corpuscles are concerned in involution ; 
he noticed that they are situated in the neighbourhood of the vessels, and thought the 
central cavity an artificial product, and that there is no change of gland cells to fat 
cells; he said that chromatin crystals are often found in the gland. 
Gunsberg (42), 1857, found crystals of hsematoidin in the thymus, and cells con¬ 
taining blood corpuscles identical with those that are met with in the spleen. 
Funke (58), 1858, came to the same conclusion as Hewson (11) and Bischoef (29) 
in regard to the function of the thymus, considering it an organ for the restoration of 
the morphological elements of the blood. He concluded that some of the gland cells 
are transformed into fat cells. 
Friedleben (3), 1858, who is the author of a valuable monograph, the labour of 
many years, found, in the thymus of the Calf, a central string in each cervical portion. 
He thought that there is no duct, and that the organ consists of closed follicles. In a 
postscript, however, he described hollows. He noticed that the richness of the vessels 
had been greatly over-estimated. He gave weights of the thymus during various 
periods of life, to prove that it increases up to the end of the second year. He 
noticed concentric corpuscles in the thymus of the foetus, but did not consider them 
important factors in involution; he concluded that involution partly arises from the 
connective tissue pressing on the follicular wall, and partly from a fatty change of 
the contained tissue. In involution he noticed an increase in the size of the coats of 
the vessels ; and imagined that this is due to a change in the nerves. Friedleben 
quoted and confirmed Restelli’s (59) observation that the blood of the thymic vein, 
in Calves three to four months old, contains numerous elements of the thymus; and 
that the blood coming from the thymus has a marble-like appearance. He failed to 
notice any difference between the contents of the lymphatic vessels, and of the lymph 
vessels of other parts; and stated that the number of lymphatics is much exceeded by 
that of the veins. He removed the thymus in young animals as Restelli (59) had 
previously done, and found that the animals lived and increased in weight very rapidly, 
and that in the blood of these animals there were more colourless blood corpuscles 
than usual. 
His (46), 1859, described, and gave very good figures of, the connective-tissue- 
