302 SUMMARY OF CURRENT RESEARCHES RELATING TO 



may produce by their metalwlism grains of fat, vacuoles of glycogen 

 crystals of pigment. 



In another communication * the author describes the minute structure 

 of the internal rods of the organ of Corti. 



New Form of Nerve-ending in Sinus Hairs of Horse.t — Jean 

 Zaczek finds in these hairs a kind of terminal club in the internal and 

 external lamella of the hair-follicle. The simplest terminal clubs consist 

 of an axis-cylinder, an " internal club," and a connective-tissue capsule. 

 The axis-cyiinder has a coiled course, and ends at the upper pole of the 

 club in a knob-like thickening. The " internal club " is a sort of proto- 

 plasmic sheath. Then there are concentric layers forming the connective- 

 tissue capsule. Complications occur by the division of the axis-cylinder 

 or the ramifications of its fibres. Sometimes there is an approximation 

 to the so-called Golgi-Mazzoni corpuscles in the subcutaneous tissue of 

 man. 



Reissner's Fibre. |—G. E. Nicholls discusses the fine cylindrical 

 thread, called Reissner's fibre, which lies in the central canal of the brain 

 and spinal cord of practically all Vertebrates. In arises in the brain 

 beneath the posterior commissure from a tract of modified ependyma, 

 for which the name commissural organ has been proposed by Dendy and 

 Nicholls. From the ventricular surface of this organ a number of fine 

 long cilia-like processes grow out and coalesce to form a single thread — 

 of very high refractivity, and apparently structureless. In life it exists 

 normally under considerable tension, and it would seem that breakage of 

 the fibre brings about a temporary loss of control over the pose of the 

 body when at rest, and probably also when in motion. The author olfers 

 some confirmation of Dendy's theory that the fibre is concerned in 

 regulating the flexure of the body. 



Mitochondrial Structures in Human Epidermis. §— CI. Regaud and 

 M. Favre show that the mitochondrial structures in epidermic cells are 

 polymorphic (granular, bacilliform, and filamentous), and that there is 

 strong evidence in favour of regarding the spirally-twisted filaments of 

 Herxheimer as also mitochondrial. 



Peculiarity of Epithelium of Gall-bladder. Ij—G. D'Agata de- 

 scribes an internal reticular apparatus in the epithelial cells of the 

 gall-bladder of the guinea-pig and other animals. It lies like a web 

 between the nucleus and the" free margin of the cell, and seems to be 

 quite distinct from the mitochondrial structure. 



Testicular Epithelium in Mice and Rats.lf — Bruno Monterosso 

 finds that starving or treatment with dry extract of thyroid acts at first 

 as a stimulus to the metabolism of the testicular epithelium. The 

 quantity of fat increases with the number of cell-divisions. Prolonged 



* Comptes Rewdus, cliv. (1912) pp. 135-8 (3 figs.). 

 + Bull. luternat. Acad. Sci. Cracovie, 1911, pp. 724-6 (1 pL). 

 + Anat. Aiizeig., xl. (1912) pp. 409-32 (2 pis. and 1 fig.). 

 § O.K. Soc. Biol., Ixxii. (1912) pp. 328-31 (2 figs.). 

 II Arch. Mikr. Anat., Ixxvii. (1911) pp. 78-81 (2 figs.). 

 t Arch. Biol., xxvii. (1912) pp. 35-62(1 pi.). 



