2 
fibres by Ewatp and Kttune') who found that they resisted pan- 
creatic digestion and, accordingly, it was assumed that they consisted 
of white fibrous tissue. More recently, however, MALL ?) has emphasized 
the fact that the interstitial tissue of many glands and organs consists 
of a network of branching and interlacing fibrils that have no definite 
connection with the connective tissue cells. He found, moreover, that 
these fibrils are neither white fibrous nor yellow elastic tissue, and 
owing to differences of a chemical nature and to reactions distinct 
from either of them, he formed of them a new interstitial tissue 
which he designated as Reticulum. Reticulum has a wide distribution 
throughout the body especially in the splanchnic area and is easily 
differentiated from yellow elastic tissue by the fact that it resists 
pancreatic digestion. It is characterized in a general way by being 
more resistant than white fibrous tissue and yields on manipulation 
a characteristic residue, Reticulin?). If boiled in !/, °/, HCl tendon 
is dissolved in one minute, while it takes about eighteen minutes for 
reticulum to go into solution; and, similarly, when a !/, °/, solution 
of KOH is used, the reticulum is dissolved in thirty: five, while tendon 
is destroyed in two minutes. It appears, however, that the resistance 
of reticulum in different situations is liable to vary for in a later 
paper Mat‘) states that he finds in the spleen two types of reticu- 
lum, the most resistant and the least resistant. In dilute acids tendon 
and reticulum swell but the sharp contour of the fibrils is brought 
back when they are stretched by pressing on the cover glass. These 
reticulated tissues have been studied by methods of maceration, di- 
gestion, staining, and precipitation (OPPEL’s modified GoLGI method) 
and the different procedures have yielded apparently quite different 
results. But recent work, however, seems to indicate that these results 
will be brought more or less into harmony, inasmuch as apparent 
differences in structure and arrangement seem to result simply from 
differences in manipulation. In this connection it is interesting to 
note that OppreL®) has accepted Maur’s observations and has ac- 
knowledged that the “Gitterfasern” which he found in the liver 
with his silver method are identical with the reticulum fibrils which 
1) Ewaup und Künne, Verhandl. d. Naturhist.-med. Vereins Heidel- 
berg, Bd. 1. 
2) Marz, Abhandl. d. Kgl. Sachs. Ges. d. Wiss., 1890, and the Johns 
Hopkins Hospital Reports, Vol. 1. 
3) SIEGFRIED, Habilitationsschrift, Leipzig 1892. 
4) Marz, The Johns Hopkins Hospital Bulletin, 1898. 
5) Orrer, Verdauungsapparat. MERrKEL-Bonner’s Ergebnisse, 1898. 
