490) ‘ORREN LLOYD-JONES AND F. A. HAYS 
The aim was to make observations at four-hour intervals, but 
this was approximated in only a very general way; in some cases 
in the earlier part of the work but a single observation 20 hours 
or so after the semen was secured was recorded. We have dis- 
covered no convenient way in which this data may be condensed 
or summarized beyond the ‘note-book’ form in which it is given. 
An average of the first four-hour interval encountered as one 
passes downward in each ‘service’ column, at which no sperm 
are active, suggests itself as an expression of the average duration 
of motion at each service. But averages calculated in this way 
conceal the really significant more rapid dropping off in per cent 
of active sperm which is unmistakable in the semen from high- 
service groups. The table can best be studied by reading across 
the rows set opposite each four-hour interval and comparing the 
per cent of active sperm in semen from the different services at 
this number of hours after the several samples were taken. For 
example, in case of male No. 1 on January 1, 1917, the fresh 
semen (0 hours) from 1st service showed 97 per cent of the 
sperm active; from 20th only 90. In the next lower row we &ee 
that after standing on the table four hours the Ist service 
semen showed 95 per cent active, the 20th 50 per cent. At 16 
hours after recovery there were 35 per cent active from Ist serv- 
ice, but all sperm were inactive in the specimen from the 20th 
service. But this more rapid decline in per cent active sperm 
in semen from more advanced service groups is again by no means 
universal with the data and in some cases the persistence of 
activity in semen from 15th or 20th service is fully the equal 
to that from the Ist (Male No. 1, July 9, for example). 
A factor which gravely interferes with the precision of these 
results is that of bacterial growth and its products. No means 
to use sterile apparatus were at hand, and in spite of scrupulous 
cleanliness putrefaction of course eventually set in. In a few 
cases sperm will continue to move even though odors indicate 
that degenerative processes are well established, but almost 
always, motion has ceased before bacterial growth has proceeded 
‘thus far. Nevertheless sperm may be influenced by the incipi- 
ent stages of putrefaction in the fluid and the onset of this process 
was not under our control. 
