REPORT OF THE STATE ENTOMOLOGIST 1903 99 



her eggs. The large proportion of females is well shown in the 

 trap lantern record, where but 87 males were taken to 485 females. 

 The great activity of the females and the large number of them 

 attracted to lights must diminish materially the value of the trap 

 lantern as a means of destroying insect pests. 



Oviposition and larval habits 



The females possess a sharp ovipositor which is capable of in- 

 flicting a slight wound. Its sharpness appears to be mainly for 

 defensive purposes, as the eggs are deposited usually on the skin 

 of the host, to which they firmly adhere by means of a cement 

 or glue extruded at the moment of oviposition. The deposit of 

 the egg by E r e m o t y 1 u s macrurus has been graphically 

 described by Trouvelet as follows 1 : " When an Ichneumon de- 

 tects the presence of a worm, she flies around it for a few seconds, 

 and then rests upon the leaf near her victim ; moving her antennae 

 very rapidly above the body of the worm, but not touching it, and 

 bending her abdlomen under the breast, she seizes her ovipositor 

 with the front legs, and waits for a favorable moment, when she 

 quickly deposits a little oval white egg upon the skin of the larva. 

 She is quiet for some time and then deposits another upon the 

 larva, which only helplessly jerks its body every time an egg is 

 laid." Eight to ten eggs are laid in this manner. A few days 

 later they hatch and the larvae make their way under the skin 

 of their victim, feeding on the fatty portions of the host at first, 

 but later most of the tissues are devoured. The miserable victim 

 of these parasites drags out a weary existence and usually per- 

 ishes in^the pupal state, rarely before. As a single larva will 

 provide sustenance for the development of but one or two para- 

 sites, the weaker. ones perish. 



There is on the front tibia of Ophion an articulated, apical 

 spine, a structure common to many Hymenoptera, which is pos- 

 sibly connected with the method of oviposition narrated above. 

 This articulated spine is curved toward the tarsus near the apex, 

 and might consequently be used for holding the ovipositor, be- 



x 1868 Am. Nat. 1 :89-91. 



