1922. No. 4- MIOSIS CONGENITA SEU MICROCORIA FAMILIARIS. I9 



ening fillets, unlike those of Heerfordt, are built up of plain-muscle cells 

 of the ordinary mesodermal type. 



The smoothness of the posterior surface of the iris in my material 

 is probably to be understood as a direct consequence of the very defective 

 development of the dilatator. In man the dark brown, almost -black sur- 

 face of the normal iris appears smooth to the naked eye, and it is only 

 under the microscope — preferably binocular — and a very strong light 

 that the two groups of radial folds appear in distinct relief. As no illustra- 

 tion of this condition is given in opthalmological, and only very rarely in 

 anatomical, text-books,^ I have thought it desirable to give an illustration of 

 the posterior surface of a normal iris, from a girl of 17, as seen under a 

 binocular microscope (fig. 15), in order to show how entirely different are 

 the conditions in our case of Miosis congenita (fig. 14). 



Fig. 15 shows the two systems of radial folds well developed, both 

 Schwalbe's contraction-folds behind the sphincter and the structural folds 

 which begin 1.5 mm. from the margin of the pupil, and become broader 

 and flatter towards the margin of the ciliary body. Here, too, there are some 

 fine circular folds which are only formed when the pupil is dilated. In 

 Miosis congenita (fig. 14) the circular folds are therefore entirely absent, 

 and there are only indications of a few shallow radial folds. Notwithstand- 

 ing the strong binocular magnification, the posterior surface of the iris 

 here appears almost smooth. 



With regard to the appearance of the stroma I should state that in 

 the pupillary part it was best developed, while in the intermediary part 

 of the iris it presented a peculiar appearance, resembling the fadal mucoid 

 {or gelatinous) tissue. In front of the sphincter the connective tissue con- 

 tained an abundance of cells, but behind it it had few cells and was scle- 

 rotic. There was no sign of inflammatory conditions in it In the middle 

 part of the iris the mucoid ground-substance was sometimes so prominent 

 that in the celloidin sections I thought it possible that the epithelium had 

 become detached from the stroma, and that in consequence some celloidin 

 had entered and filled the interstice, and had taken a faint shade of colour. 

 On closer examination, however, this proved not to be the case. It was 

 the peculiar homogeneous ground-substance that I was looking at, and in 

 which lay the few fine fibrils and the cells. There was nothing remark- 



1 Best in Maximilian .Salzmann's "Anatomie und Histologie des Menschlichen Augapfels 

 im Normalzustande". Vienna, 19 12. Taf. VllI, 2. .See also Merkel's "Die Anatomie 

 des .Menschen", Atlas zur fünften Abt., fig. 107. 



