296 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Papillary Ridges of Monkeys and Men.* — Dr. D. Hepburn con- 
cludes that the papillary ridges and their intervening furrows are 
adjuncts to the prehensile function and power of the hands and feet, as 
ivell as arrangements associated with increasad sensibility and discrimina- 
tion of the sense of touch. The eminences on which papillary ridges 
form designs or pattsrns are specially developed areas raised above the 
general level of suriounding parts. They are also special developments 
in relation to the prehensile function. This accounts for their constancy 
in the hands and feet of animals which have these organs modified for 
prehension. The “ design ” which covers each of these eminences has 
its character determined by the position, shape, and dimensions of the 
particular eminence. 
Red Blood-Corpuscles of Embryo Chick.f — Dr. A. Dehler observes 
that the red blood-corpuscles in a chick embryo a few days old show, 
in regard to central corpuscles, the same conditions as many other cells, 
especially leucocytes. In their processes of division, like cells slightly 
influenced by their surroundings, they assume the simplest, that is, the 
spherical form. In their resting stage, with increase of their surface, 
they exchange this for a lenticular form, mainly in adaptation to an in- 
creased function of oxygen-transport. 
Vacuolation of Fat-Cells.J — Dr. A. Sack has studied a wide series 
of fat-cells, and finds that, as a normal process, quite apart from atrophy, 
spherical or ellipsoidal vacuoles are formed within the nuclei, attain a 
certain size and tension, and then pass out into the cell-substance. A 
depression or hole, left by the extrusion of the vacuole, persists for some 
time ; and after one vacuole has migrated another begins to be formed. 
Structure of the Retina. § — Prof. A. S. Dogiel has studied the 
minute structure of the retina in various birds, using a modification of 
the methylen-blue method. One of his important general results is that 
the protoplasmic processes and the axis-cylinder process of each cell con- 
sist of the same component substances (chromophilous substance, ground- 
substance, and threads), but in different quantities. In the axis-cylinder 
processes there are only traces of chromophilous and ground-substances, 
the greater part consisting of threads. In the protoplasmic processes 
the chromophilous and ground-substances are much more abundant. 
Structure of Herve-Cells in Spinal and Central Ganglia. || — Prof. 
W. Flemming corroborates his previous conclusions that the cells of 
spinal ganglia in Mammals show a distinct threadwork. The fibrils 
have a very irregular wavy course, while in central nerve-cells they run, 
on the whole, straight. For the details we must refer to the original 
paper. 
Spinal Ganglia of Mammals.1[ — Drs. A. Spirlas and G. Sclavunos 
find that the spinal ganglia of Mammals (goat) include, during embryonic 
life, at least, a number of multipolar cells. In some cases the cells 
* Sci. Trans. E. Dublin Soc., v. (1895) pp. 525-38. 
f Arch. f. Mikr. Anat., xlvi. (1895) pp. 414-30 (1 pi.). 
X Tom. cit., pp. 431-78 (1 pi., 8 figs.). § Tom. cit., pp. 394-413 (1 pi.). 
|| Tom. cit., pp. 379-94 (1 pi.). 
Anat. Anzeig., xi. (1896) pp. 629-34 (6 figs.). 
