Preston Kyes 43 



method, the fibrils may be stained brown and with Mallory's stain a 

 blue-black. I have not been able to obtain similar reactions with the 

 white fibers of tendon. 



Such staining reactions would seem to be responsible for the con- 

 tinued descriptions of elastic fibrils within the pulp cords, the walls of 

 the capillary veins and the j\Ialpighian follicles. Fibers within all of 

 these structures may be brought into view by overstaining with the so- 

 called elastic tissue stains. The staining reaction of such fibers, 

 however, is not that typical of the elastic fibers seen within the tra- 

 becule and the arterial walls, and unlike elastic fibers, they resist pan- 

 creatin digestion. I quite agree with Hohl' that the fibrils within the 

 walls of the capillary veins of the human spleen described by v. Ebner "" 

 as elastic tissue cannot be such, since they resist pancreatin digestion. 

 In addition their staining reactions are those of reticulum found else- 

 where. 



SUMMAEY. 



1. Within the lobule of the human spleen there is a delicate network 

 of fibrils continuous throughout the pulp cords and the Malpighian 

 follicles. 



2. The fibrils of this entire network are reticulum in the sense of 

 Mall. 



3. The fibrils encircling the capillary veins are an integral part of 

 this reticulum network and are not elastic tissue. 



4. The so-called specific elastic tissue stains yield a positive reaction 

 with reticulum as well as with elastic fibers. 



SHohl, E. : A7iat. Am., Bd. XVII. 

 i»v. Ebner: Anat. Anz., Bd. XV. 



