754 
dwarf of O. nanella X biennis with the pollen 
of an ordinary O. nanella and got a culture of 
O. (nanella < biennis) K nanella = O. nanella 
which contained a high percentage of healthy 
plants. They began flowering when only 20 
em. high, the first flower appearing at a height 
of 10 em.; whilst O. Lamarckiana reached 
1.50 m. before flowering, the first flower open- 
ing about 80 em. above the soil. All their 
leaves were as narrowly elliptical and as 
clearly stalked as those of the Lamarckiana 
itself, whilst the flowers were free from those 
abnormalities which usually accompany the 
dwarfish stature. 
Thus we see that the discovery of Zeylstra, 
far from diminishing the value of @nothera 
nanella as a real and (in an experimental way) 
most useful mutant, has given the means of 
cultivating it in as healthy a condition as may 
be required. Hueco DE VRIEs 
BEHAVIOR OF SPERMATOZOA IN PLASMA 
THE recent article of Loeb and Bancroft’ 
and of De Meyer’ in which their observations 
upon the behavior of spermatozoa in various 
sorts of solutions, such as extracts of eggs of 
the same species (De Meyer, eggs of Hehinus 
microtuberculatus; Loeb and Bancroft, eggs 
of the common fowl), colloids, acids, alkalies, 
hypo- and hypertonic solutions, egg-albumen, 
blood serum and Ringer solutions are de- 
scribed open up a most interesting field for 
investigation. During the past summer while 
occupying a table at the Marine Biological 
Laboratory, Woods Hole (for the use of which 
I am indebted to Professor F. R. Lillie), I at- 
tempted to grow spermatozoa of Arbacia 
punctulata, Mytilus edulis and Modiolus mo- 
diolus in various solutions, some of which 
being listed above as used by these other 
workers. 
1 Journ. Exp. Zoology, 12: 381. 
* Arch. Biol., 1911, Bd. 26, H. 1, pp. 65-97: 
‘“Observations et expériences relatives a 1’action 
exercée par des extraits d’eufs et d’autres sub- 
stances sur les spermatozoides.’’ I have seen only 
Robert Lewin’s review in the Zentralb. fir Bio- 
chemie und Biophysik, XII., No. 19/20, of De 
Meyer’s paper. 
SCIENCE 
[N.S. Vou. XXXV. No. 906 
On August 2, I centrifuged Limulus blood 
plasm and made a hanging drop from the 
upper layer, which examination showed to be 
free from cells; into this drop I introduced a 
few sperms from Arbacia. Great difficulty 
was experienced in attacks of bacteria and 
many of the preparations were discontinued 
the following morning. The slides were sealed 
with vaseline, as in the usual culture mount, 
and left at room temperature. By the eighth 
of August there was no movement in the 
sperms, although it had persisted up until 
that time and therefore the copper component 
of the blood of this animal does not seem to be 
toxic for Arbacia sperms, but none of the phe- 
nomena about to be described from mounts 
in different media were observed. 
On August 5, a culture was made in the 
sterile agar medium, made according to the 
customary bacteriological formula, diluted so 
that it was liquid but highly viscid at 20° OC. 
The spermatozoa lived only a short time and 
were seen to disintegrate within 24 hours. It 
may be stated that the reaction of the agar 
was estimated only roughly by an indicator 
and not titrated, so that I am not certain 
whether the medium was suitable from this 
standpoint. Care was taken to render the sea- 
urchins as free from bacteria as possible, the 
tests being washed off with HgCl,, 1:1,000 be- 
fore the cuts were made and sterile sea-water 
was used to receive the testes after extirpa- 
tion. The mounts remained sterile through- 
out the time of observation, showing that the 
testes are bacteria-free, as one would suspect. 
The plasma of a Norway rat was then tried 
on August 8 and this was prepared by centri- 
fuging the blood of the rat in paraffin-lined 
tubes at about 8°-10° C. The plasma clotted 
when the hanging drop was made at room 
temperature, but suflicient time elapsed be- 
fore the plasma clotted for the introduction of 
the sperm. The behavior of the sperm-heads 
was discovered to be quite like that described 
by Loeb and Bancroft for the sperm of the 
fowl, for the heads enlarged, became less dense, 
and distinct chromatin granules were visible, 
even in unstained preparations, resembling 
the nuclei of the spermatids of certain insects 
