■596 SUMMARY OF CURRENT RESEARCHES RELATING TO 



epithelio-muscular cells of Ccelentera, the epithelial myoblasts of higher 

 Metazoa, and the epithelio-muscular cells of higher Metazoa. 



Structure of Nucleus in Smooth Muscle.* — K. Munch had his 

 attention arrested by an apparent transverse or oblique striation in the 

 nucleus of smooth muscle-cells of cat, rabbit, guinea-pig, and other 

 mammals. Careful investigation showed that the appearance was due 

 to a spiral of chromatin making from 3^-15 coils within the achromatin 

 matrix. Munch regards this as the normal condition of the resting 

 muscle-nucleus, but there is need for further observations on other 

 objects. 



Cross-Striped Muscle.t— K. Munch maintains that the so-called 

 cross-striping of muscle is the optical expression of the spiral arrange- 

 ment of the anisotropic substance. To this theory of muscle-structure 

 he appends a re-interpretation of the phenomena of contraction. 



Intracellular Threads in Nerve-Cells.l — E. Holmgren re-describes 

 the so-called " intracellular threads " in the nerve-cells of Lophms 

 piscatorius. His observations differ so much from those made by Solger 

 on Torpedo that we are bound to suppose that the two sets of threads 

 are quite different structures. The " threads " in Lophius are probably 

 special differentiations of nerve-cells that form capsular processes. They 

 are perhaps comparable to the filamentous differentiations of glia-cells. 

 They do not represent, as in Torpedo, the hyaline crystalloid contents of 

 the trophospongium-canaliculi ; they are not hyaline but composed of fine 

 filaments ; they have not a granular composition ; they never lie in 

 preformed canaliculi, but are always accompanied by capsular processes. 



Trophospongia in Glandular Cells. § — E. Holmgren recalls his dis- 

 covery of canalicular structure in liver-cells of the guinea-pig, which 

 he regards as trophospongia! canaliculi,— dense or loose networks of 

 very fine tubules with parallel walls. He has found the same kind of 

 trophospongial canals in the cells of Langerhans's islands in the pancreas 

 ■of the white mouse. He vindicates his particular interpretation of the 

 canaliculi against those suggested by others. 



Structure of Red Blood-Corpuscles. || — Vladislav Ruzickahas studied 

 the erythrocytes of frog, guinea-pig, and man. He points out that there 

 are many gaps in our knowledge of the exact structure of the erythro- 

 cyte, of the membrane thereof, of the relation of the hsemoglobin to the 

 ■cytoplasm, and as to the nucleus in mammalian erythrocytes. He has 

 tried to fill up some of these gaps. 



We can only notice his general conception that the red blood- 

 corpuscle includes a vegetative part, — a reticular structure imbedded in 

 a colourless matrix, — and a functional part, probably associated with a 

 peripheral haemoglobin envelope bound to a portion of the matrix. 



Axial Filament in the Adult Connective Tissue Fibril.H— P. A. 

 .Zachariades finds that the connective fibril, say in a tendon, is much 



* Arch. Mikr. Anat., Ixii. (1903) pp. 41-54 (1 pi.). 



t Tom. cit., pp. 55-107 (22 figs.). 



J Anat. Auzeig, xxiii. (1903) pp. 37-49 (7 figs.). 



§ Tom. cit., pp. 289-97 (8 figs.). || Tom. cit,, pp. 298-314 (18 figs.). 



f Comptes Rendus, exxxvi. (1903) pp. 973-5. 



