The Ohio ^J\^atiiralist, 
PUBLISHED BY 
The Biological Club of the Ohio State Uni'versity. 
Volume IV. JUNE, 1904. No. 8. 
TABLE OF CONTENTS 
York— The Embryo-sac and Embryo of Nelumbo 167 
Osborn — Formal Opening of the Lake Laboratory Building 177 
Kellei;m.\n and Jennings— Flora of Cedar Point 1S6 
Keller.man— Flora of Hen ami Chicken Islands. 1903 190 
SCHAFKNER — The Jacket Layer in Sassafras 192 
Frank— -Meetings of the Biological Club 193 
THE EMBRYO-SAC AND EMBRYO OF NELUMBO.* 
H.arl.\x H. York. 
Since the publication of Lyon’s studies on Xelumbo and Cook’s 
work on Castalia and Xymphaea, the systematic position of the 
Xympli3-aeaceae has again become a prominent question. Owing 
to the Yariety of opinions held in regard to the classification of 
this group, it was thought desirable to continue the stud\’ of the 
life history of Xelumbo lutea, although this plant has been 
described more or less completely a number of times. 
yiaterial was collected during July and August, 1902, in San- 
dusk}' Ba}', near the Ohio vState Uniuersity Lake Laboratory, at 
Sandusky, Ohio. Flemming’s stronger and weaker solutions 
and chromo-acetic solution were used as killing and fixing 
agents. On examining the ovules, it was found that in most 
cases the tissues had not been properly penetrated by these fluids. 
In the summer of 1903 more material was collected, near the 
jilace already mentioned, which was killed and fixed in Kleineii- 
berg’s picro-acetic and picro-sulphuric solutions and was found 
to be preserved in good condition. The ovules were passed 
through the alcohols, imbedded iu paraffin, and serial sections 
were cut 10-12 mic. thick. For staining several reagents were 
used : Delafield’s heamotoxylin, Heidenhain’s iron alum haemo- 
toxylin, analin safranin and gentian violet. All of these stains 
were successful, the last named stain giving the best results. 
Considerable difficulty was experienced, in that a great many 
ovules had failed to develop embryo-sacs and others had not been 
fertilized. Quite a large number of slides were prepared and 
most of the points mentioned were observed a number of times. 
This work was commenced under the direction of Prof. Mel. 
T. Cook in the De Pauw Universit\’ Botanical Laboratory and 
'‘Contributions from the Botanical Laboratory of Ohio State University. XVII. 
