118 PROC. ENT. SOC. WASH., VOL. 24, NO. 5, MAY, 1922 



ings and an excellent description of the conjunction and ovi- 

 position of one of the Odonata found on the Pacific Slope. 

 Needham in a volume entitled "Aquatic Insects in New York 

 State," published in 1903, at page 225 says in reference to the 

 species represented in the photograph, "The females descend 

 to stems of more or less completely submerged aquatic plants 

 (Elodea), and unattended by the males, insert their eggs into 

 the green stems just below the surface of the water." 



In the case of the form described bv Kennedy, the female is 



J J ' 



accompanied, as he states, during the act of oviposition, by the 

 male still clasping her by the prothorax. 



In the act which the photograph represents the male, shown 

 in the lower figure, seizes the female by the prothorax and 

 copulation ensues The sexual organ of the male is located 

 on the second post-thoracic segment; that of the female being 

 located at the extremity of the abdomen. 



That the female of many species of the Odonata deposits 

 her eggs in minute incisions in the stems of aquatic plants is a 

 fact known to specialists. I have before me a dried piece of 

 the stem of a yellow water lily (Nenuphar), which under the 

 magnifying-glass shows that it is covered all over with deep 

 pittings made by the ovipositors of female dragonflies. These 

 pits are surrounded by circular elevations of the tissue of the 

 plant, which continued to grow after the incisions were made. 

 They are somewhat crater-like in appearance. The female 

 in the act of oviposition submerges the anal extremity of her 

 abdomen below the water-line, continuing to descend as she 

 makes incision after incision, in which she deposits the eggs, 

 until she is submerged up to the head, and she frequently 

 descends further, until she is completely submerged below the 

 surface, in which submerged position she may remain for as 

 much as an hour, as I am told by one of my colleagues. Where 

 the female is accompanied by the -male both of them may be 

 completely submerged during the act of oviposition for a long 

 time. These creatures, the airy flight of which, as they dash 

 about in the sunshine in quest of their prey, consisting of midges, 

 gnats, and mosquitoes, would not be suspected by one who has 

 thus seen them, to be capable of living under water, but they 

 not only do this in the larval stage continuously, but also in 

 copulation for long periods after they have emerged as imagoes. 



WEEVILS OF THE GENUS APION INJURIOUS TO BEANS IN 



MEXICO. 



BY H. F. WICK.HAM. 



While engaged upon the principal subject of the investiga- 

 tion of the Mexican bean beetle, it was noticed almost from the 



