THE MIDDLE EAR. 53 



tympani, and which here presents the same relations to the 

 periosteum as it there does to the membrana propria. Here 

 also it consists of extremely minute fibrils, which collectively 

 form a framework of trabecuke and a foraininated membrane, 

 which, like the periosteum, includes large spaces filled with 

 nerves, bloodvessels, and lymphatics. At various points of 

 the cavity this fibrous framework becomes detached from the 

 periosteum, in order to stretch across the cavity from one 

 bony prominence to another. These bridges serve at the same 

 time as supports for numerous capillaries running from point 

 to point, and are everywhere covered by an epithelium which 

 is ' continuous, where they are attached, with that of the 

 mucous membrane. Thereto belong the ligamentum mallei 

 superius, the ligamentum mallei externum et posterius, and 

 the posterior pocket of the membrana tympani. The liga- 

 mentum mallei anterius is composed of thick bundles of fibrils 

 resembling those of tendinous' tissue, and forms with the 

 ligamentum mallei posterius the so-called axial cord, which 

 at the same time constitutes the axis of revolution of the 

 malleus (Helmholtz, 11). Moreover certain trabeculae which 

 are stretched between the numerous bony processes on the 

 floor of the tympanic cavity belong to the same category. A 

 trabecular framework which I have very frequently found in 

 the vicinity of the stapes is deserving of special mention. 

 This passes from the eminentia pyramidalis, which is a bony 

 projection, to the semi-canal of the tensor tympani projecting 

 sometimes strongly into the free space of the tympanic cavity 

 and forms a more or less deep groove or nick with the 

 posterior superior margin of that canal. Proceeding from the 

 free border of this band I frequently saw several trabeculae, often 

 communicating with each other, span the groove, and pass to 

 be inserted either at the base or into the posterior crus of the 

 stapes. 



Peculiar bodies, differing considerably from each other 

 in external form and size, but upon the whole exhibiting 

 the same structure, present themselves in this framework, as 

 well as on the floor of the tympanum and in the ligamentum 

 mallei superius, which extends from the tegmen tympani to 

 the caput of the malleus. In the more simple forms of these 



