Februakt 19, 1915] 



SCIENCE 



293 



The perforatorium of the ripe spermatozoon 

 tapers off in the form of a corkscrew. In 

 Ringer's fluid it swells into a bleb-like process 

 andl as such' is figured by Duesberg and 

 Morse. The tail has two movements, a whip- 

 like lash and a twirl, its base being used as a 

 pivot. These two movements whirl the sper- 

 matozoon forward in a corkscrew fashion. It 

 may be noted that the lashing movement of 

 the spermatozoon tail is directly comparable 

 to the waving of the axial filament within the 

 spermatid. 



In conclusion I wish to emphasize the fol- 

 lowing points drawn from this and from my 

 previous paper: 



1. As far as nuclear structures are con- 

 cerned the study of fresh material corrobo- 

 rates, in many interesting details, the observa- 

 tions made in fixed material. Both methods 

 are necessary for a proper understanding of 

 the structures. Our present fixing methods^ 

 however, are useless for the study of cyto- 

 plasmic and mitochondrial structures and 

 should be replaced by the study of fresh ma- 

 terial. 



2. " Physiological " salt solutions are more or 

 less injurious to the cells studied which are 

 normally bathed by organic fluids, i. e., liquid 

 colloids. 



3. Puncture of a cell by a needle causes ir- 

 reparable injury. When the injury is slight 

 it at first hastens the normal reversible 

 changes in the physical states of the colloids 

 in the cell but soon transforms them to an ab- 

 normal condition from which the cell does not 

 recover. 



4. Injury to the cell is always followed by 

 swelling accompanied by an increased inhibi- 

 tion of water. 



5. A tension exists in the cell during di- 

 vision which is immediately lost when any 

 part of the cell is torn. 



6. A m oeboid activities are prevalent among 

 the germ cells. In this way extensive move- 

 ments occur within the cysts of the testis 

 follicle. When set free in a liquid medium, 

 the amoeboid processes are very soon retracted 

 and the cells assume a spherical shape. 



The movement in waves of the axial fila- 

 ment of the spermatid starts at the conical 

 knob on the nucleus and accompanies the un- 

 coiling of the filament from the surface of the 

 Nebenkern. 



7. The staining of the mitochondria by 

 Janus is probably not due to a chemical com- 

 bination. In time the stain fades out of the 

 cell. If the stained structure be brought into 

 immediate contact with a liquid it is washed 

 out almost immediately. 



8. Janus green, if used in sufficient con- 

 centration, will stain the nuclear structures. 

 The dye is reduced to the red safranin even 

 in the presence of abundant air. This has 

 been observed in all stages of the germ cells 

 and also in motile spermatozoa. Such cells, 

 however, soon die. Dead cells take up the 

 blue stain readily, the nuclear structures 

 showing beautifully. 



9. Janus green, being a basic dye, coagu- 

 lates albuminous substances. In living cells 

 this coagulating effect is very noticeable. 

 The stain, therefore, can not be used as the 

 sole means for identifying mitochondria. 



10. The mitochondria, in the Orthopteran 

 germ cell, are in accord with those studied by 

 the Lewises^ in the tissue cells of the chick. 

 They can not be classed as persistent struc- 

 tures. They pass from a granular stage into 

 strands; they may coalesce into homogeneous 

 masses ; they disappear and reappear and must 

 be merely changes in physical states of the 

 colloids which compose the cytoplasm. 



Egbert Chambers, Jr. 

 Univeksity of Cincinnati 



some new cases of apogamt in ferns, 

 preliminary note 



Several cultures of Aspidium isussimense, 

 Pellwa adiantoidis and Lastrea clirysoloha 

 were made beginning June 25, 1914. The 

 spores were sown on sphagnum, which was 

 first placed in small stender dishes, saturated 

 with a one-tenth-per-cent. Knop's solution, 

 and then thoroughly sterilized in an oven. 



3 M. E. and W. H. Lewis, ' ' Mitoehondria in 

 Tissue Culture," Science, N. S., XXXIX., p. 

 330, 1914. 



