40 University of California Puhlications in Zoology [Yoh. 13 



ably lowered. There is a very slight loss, however, as a fog-like con- 

 densation occurs at the upper end of the tube which is strongly acid. 

 Occasionally also the odor of chlorine gas is observable in the room 

 while the bath is being heated up, especially if it has been cool for some 



Fig. 1. The new paraffin bath in oj)ei'ation. 



time. Possibly it may indicate a change which would ultimately affect 

 the boiling point of the chloroform but if this proves true it will be 

 very simple to use new chloroform. Our experience indicates that this 

 will not have to be done until after many months, if at all. 



