3 8 4 



THE QUARTERLY REVIEW OF BIOLOGY 



of the syringe into the midst of the 

 yellow sperm. This is about all taken up, 

 leaving the collapsed bulb neatly empty. 

 The virgin queen still resting on the 

 operating-table, and having been fed, is 

 now brought into the magnified field, 

 and placed with the tip of the abdomen in 

 the center of the field, and pointing toward 

 the syringe. The operating-table is made 



vered into such position that when 

 allowed to open slightly they push back 

 the plates, and expose to view the sting, 

 sting palps, rectum and vulva. While 

 the left hand holds the vestibule open 

 (fig. 6) with the tweezers, the right hand 

 operates the controls of the microma- 

 nipulator so that the tip of the syringe 

 stands just over the opening of the oviduct, 



Fig. 6. Showing the Position of the Operator While at Work 

 Both elbows rest on the desk, and the left hand is further steadied against the stage of the microscope 



fast in this position by a rubber band 

 passing over it and underneath the table. 

 The left hand grasping a pair of the 

 finest pointed tweezers, and the right 

 hand holding some moderately sharp 

 applicator, such as a dissecting needle, 

 now cooperate to pry apart the genito- 

 anal plates of the queen, an operation 

 which some queens resist with remarkable 

 force. The tweezers are gently maneu- 



and then enters it to the depth of about a 

 millimeter. The plunger is now slowly 

 advanced till the semen is all deposited 

 within the queen. Finally, as the syringe 

 is backed away, the droplet of mucus 

 which, it will be recalled, was taken up 

 ahead of the semen in loading, is the last 

 to be discharged, and is left to thicken 

 in and over the' vulva as a plug to prevent 

 any back flow and to shut out the air. 



