Otto Glaser

A QUALITATIVE ANALYSIS OF THE EGG-SECRETIONS AND EXTRACTS OF ARBACIA AND ASTERIAS

1. In corroboration of F. R. Lillie, it was found that the egg-secretions of Arbacia punclulata exert a chemotactic effect on sperm, and activate, agglutinate, and paralyze them.2. The egg secretions of Asterias forbesii behave in a similar manner toward Asterias sperm.3. Arbacia secretion activates, agglutinates, and paralyzes Asterias sperm, and Asterias secretion has the same effects on Arbacia sperm.4. Paralyzed sperm may be reactivated but not reagglutinated.5. The egg secretions test negatively for reducing substances and do not give the usual protein tests although they were found to be faintly positive to the acid tests and the xanthoproteic. This may be due to traces of the egg jelly.6. Agglutination may be gotten with dry egg powder.7. The agglutination reaction very possibly depends on a surface effect.8. More soluble substances escape from the egg of Arbacia in hypertonic sea-water and in sea-water infected with sperm, than from unfertilized eggs in normal sterile sea-water in the same length ...

THE CHANGE IN VOLUME OF ARBACIA AND ASTERIAS EGGS AT FERTILIZATION

pages that follow I wish to present the evidence for this assertion in some detail, since for the present at least, it must stand alone. Strongylocentrotus (purpuratus?) shows no recognizable loss of volume according to Loeb (o8) but this result does not contradict mine. The loss depends on several conditions, and in Asterias is much greater than in Arbacia. This suggests the possibility of forms in which it may easily be too small to measure. The measurements of McClendon (Io), also, do not contradict mine, although they seem to show that the very eggs I worked with, on fertilization lose in a molar solution of dextrose, but remain constant, or even gain a little in sea water. The evidence consists in the determination of the diameters of I9, 20, 1O and II eggs respectively. The great variability of the ova of Arbacia punctulata, however, proves that reliable results can be gotten from a small number of eggs, only when the identical ones are measured before and after fertilization.

THE HEXOCTAHEDRON AND GROWTH

1. Certain starch grains and the polyhedral bodies of insects are hexoctahedra of the type described by Lewis for tissue cells and coagulated yolk, and by Kelvin in systems of soap bubbles.2. Compression of units visible in cellular emulsions results in aggregates of hexoctahedra. Under the same conditions the same form is postulated as either imminent or actual, at levels below the limits of visibility.3. If this extension applies to materials that control the dimensions of organisms, Marvins hexoctahedral aggregation series should be capable of replacing either organic correlative in the heterogonic equation y = bxkh. Evidence is afforded by heterogonic curves in which the Marvin series is plotted against the chick embryo and the chlorides of the chick embryo.4. The success of this test depends on two facts: (a) the heterogonic constant is the ratio between two growth constants; and (b) when isogonic aggregates of hexoctahedra are produced by organic growth, the number of layers in which the resulting ...

ON AUTO-PARTHENOGENESIS IN ARBACIA AND ASTERIAS

1. The egg-extracts as well as the egg-secretions of Arbacia and Asterias, in addition to characteristic effects on spermatozoa, are permeability increasing agents, and initiate development. For the type of initiation here dealt with I have chosen the term auto-parthenogenesis.2. Auto-parthenogenesis is blocked in Arbacia by washing the eggs in sea-water.3. A group Purple X which may be split off from the sperm of Arbacia, and which also appears in boiled egg-secretion, blocks parthenogenesis in low concentrations and fertilization in high concentrations.4. Prevention of parthenogenesis by washing can hardly be the result of an absence of fertilizin; prevention by Purple X may be the result of occupancy of the egg-receptors.5. It is not unlikely that all cases of parthenogenesis are in reality instances of auto-parthenogenesis.6. With certain minor modifications it appears possible to construct an hypothesis of fertilization in which the basal facts of the surface-alteration theory, as well as the facts...

COPPER, ENZYMES, AND FERTILIZATION

1. Nearly 37 per cent. of the copper sulphate added to sea-water is precipitated at once when the concentration is Cu = n/460.2. Two tenths c.c. normal Arbacia eggs in 75 minutes reduce the concentration of 14.8 c.c. of a Cu solution from n/1,460 to n/1,790.9.3. In this reduction the egg jelly or chorion is heavily involved.4. It was impossible to determine the quantities of copper absorbed by normal eggs and eggs without jelly because of an apparent secretion of copper by the eggs themselves.5. Therefore, the demonstration of copper in Arbacia eggs was undertaken. The copper was identified as cupric hydroxide, cupric cyanide, cupric ferrocyanide, copper xanthate, crystalline cupric sulphate, as metallic copper on tin-foil and aluminum, and finally by electrolytic precipitation under conditions under which copper and only copper could be deposited.6. The copper was localized in the egg directly by means of haematoxylin and the triple-nitrite of potassium-copper and lead. Indirectly it was localized by the ...

A SIMPLE COOLER FOR USE WITH THE MICROTOME

The microtomists ability to prepare thin paraffin sections, depends, among other things, on the hardness of his imbedding medium, and this, in turn, on the temperature of the laboratory. Usually this circumstance offers no insurmountable difficulties, but there are times and places when this is not true. To meet such conditions several devices have been suggested and used by various investigators, but we know of none so simple, or as