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Authorities differ as to the mode of oviposition among the Tipulidre; 

 and it is not improbable that there may be a difference of method in 

 different species. Curtis opined that the British species oviposited 

 while on the wing, and Miss Ormerod says that Tipula oleracea Linn., 

 oviposits in or on the surface of the ground, while Dr. Riley states that 

 he has witnessed the oviposition of an American species, Tipula trivit- 

 tata Say, and the eggs are forced into the ground by means of a double 

 pair of valves, something as in the case of our common locusts. 



In the species under consideration, the terminal abdominal segment 

 of the female is much more obtuse than in some other of the American 

 species, ending in a pair of broad, concave valves or plates, whose office 

 appears to consist in holding the eggs in place and assist in directing 

 them to within the reach of a second pair of organs. With the female 

 standing on a horizontal surface, in a natural position, the egg appears 

 to pass down the oviduct with the concave surface downward, but on 

 nearing the terminus of the oviduct the posterior end of the egg is 

 thrown under and forward, thereby bringing the concave side upward, 

 and lying, seemingly, directly under a small liguliform plate which is 

 attached only at its base. The apical portion of this triangular plate 

 appears to fit the concave side of the egg, which is prevented from going 

 too far backward by the anal valves previously mentioned. It is here 

 that the second pair of plates or valves, apparently the most important 

 appendage, is called into play. This is situated just beneath or a little 

 back of the triangular plate, their bases having very nearly a common 

 origin, and is composed of two movable valves, or claspers (whose base 

 is broadened into a thin flap, which, coming upward at the sides, forms a 

 receptacle for the egg) which, when closed together, form a hemispheri- 

 cal cup having almost the exact form of one-half of the epicarp of the hick- 

 ory nut j and each of the two parts, when opened, as faithfully represent 

 one of the valves of the epicarp. When the egg is in position on the 

 triangular plate these valves are pressed against and about it, inclosing 

 it on all sides, leaving only a portion visible along the apex; and drop- 

 ping downwards slightly, but gently, the egg is projected forth with a 

 slight snapping sound, seemingly propelled in much the same manner 

 as one would eject the pit from a ripe cherry by pressing it between the 

 thumb and forefinger. Whether the liguliform plate follows the valves 

 in this downward movement, or not, I could not determine, but think 

 such is the case, as the egg is not projected directly backward, but de. 

 fleets considerably downward. The movements of oviposition are made 

 so quickly that it is exceedingly difficult to observe the exact action of 

 the parts, and therefore I give them as they appeared to me. Further 

 observation may require a slight revision. 



I have an idea that the two elevations at the base of the liguliform 

 plate, which is drawn as seen from beneath, may serve to keep the 

 egg from slipping backward and may also assist in pushing it for- 

 ward. At the base of plate, on the under side, are two loose ap- 



