928 SUMMARY OF CURRENT RESEARCUES RELATING TO 



B. Histology.* 



Structure of Red Blood-corpuscles.t— Signori C. Cianci and G. 

 An^iolcllft have investigated the minute structure of red blood-corpuscles. 

 Their results anrce rather with those of Briicke than of KoUet. They 

 Lave been able to show the existence of two different substances within 

 the corpuscles, one forming a network, the other an amorjihous mass. 

 This has been demonstrated from fishes to mammals. 



Peculiar Fat-cells.| — Prof. H. Eabl-Riickhard described a peculiar 

 condition of the fatty tissue which he observed in sections of the head of 

 Cohitis harhatnla. In the typical fat-cell, the protoplasm of the original 

 counective-tissuc cell forms a thin envelope, and no evidence of spon- 

 taneous amoeboid movements has as yet been recorded. But inside the 

 Lead-bones of C. barhatida, active protojilasmic movements appear to 

 occur in the envelope of the fat-cell. These find expression in fine 

 " pseudopodia" radiating from the surface of the envelope, and prodiic- 

 inf» an appearance ciu-iously like that of an Actinophrys. Wenckebach 

 Las described apparently similar phenomena in the pigment-cells of 

 pelagic fish-ova. 



Karyokinesis in its Relation to Fertilization. §— Prof. W. Waldeyer 

 republishes in extended form a lecture on karyokinesis and its relations 

 to the phenomena of fertilization. Some portions have been rewritten, 

 and recent researches have been incorporated. The memoir gives an 

 account of the history of research, and presents a critical summary up 

 to date. A useful bibliography from Martin Barry's observations on 

 mammalian fecundation (1840) down to those of KultscLitzky (1888) is 

 appended. 



Reticulum of Muscle-fibre. || — Sig. P. Mingazzini reports the results 

 of his study of the supposed protoplasmic reticulum in striped muscle. 

 His material was obtained from the crayfish. His principal conclusion 

 is as follows : — The appearance of longitudinal filaments in the plasmic 

 reticulum is referable to the walls of the fibrils ; their varied forms 

 alon<^ their course are due to the contours of the clear and dark zones, 

 and of the membrane of Krause in the individual fibrils. These images 

 are produced in relation to the particular coagulations caused by various 

 reagents acting on the constituent elements of the striated fibres, and 

 especially on the refractive substance of the clear zone. The appearance 

 of transverse bars is referable to the interstitial substance of Cohnheim's 

 areas. 



Sarcolemma.lF — Prof. A. Schneider maintains that the bundles of 

 muscle-fibrils in all animals arc imbedded directly in the connective 

 tissue, and are not snrrounded by a fine structureless membrane, the 

 sarcolemma, as has hitherto been invariably stated. He describes in 

 detail some of his investigations on various animals, and affirms that 

 what, in cross-sections, has been taken for sarcolemma is, in reality, 

 only the boundary-line formed by the minute fibrillar columns coming 



* This section is limited to papers relating to Cells and Fibres. 



+ Boll. Soc. Nat. Napoli, i. (1887) pp. 67-74. 



t Arch. f. ]Mikr. Anat., xxxii. (1888) pp. 182-7 (2 figs.). 



§ Ibid., pp. 1-122 (14 figs.). 



II Bull. iSoc. Nat. Napoli, ii. (1888) pp. 24-41 (1 pi.). 



\ Zool. Beitr. (Schneider), ii. (1888) pp. 212-18 (1 pi.). 



