124 FIFTH ANNUAL EEPORT 



those of ollongifolia strikingly resemble those of conGavum^l was led 

 to suppose that the broader ones belonged to the latter. After hatch- 

 ing nothing but ohlongifoUa year after year from such eggs, and 

 noticing structural differences in the ovipositors of the two insects, 

 which seem to have escaped previous observation, I began to sus- 

 pect that the eggs of concavum were deposited in a diiierent way, and 

 experience has sanctioned the suspicion ; for, upon confining a number 

 of pregnant females of concavum^ I found that the eggs of this species 

 are always thrust into some substance, or into crevices. When fur- 

 nished with anj?- soft material, such as cork, the females crowd it full 

 of eggs. 



To be brief — as I intend to give a more extended account of our 

 Katydids in my next Report — we have in this latitude three species, 

 which are quite common, viz: The two already named, and the Nar- 

 row-winged Katydid, iPhaneroptera curvicauda^ DeGeer), easily 

 distinguished by its narrower wings, and two conspicuous recurved 

 appendages at the end of the male abdomen. If we examine the 

 ovipositor of ollongifolia^ we shall find that the terminal part is 

 armed with strong thorns, or teeth, both above and below. By means 

 of these and its jaws the female is able to rasp and roughen the stems 

 on the outside of which her overlapping eggs are laid. The difference 

 in size, and especially in thickness, which is so noticable in these 

 eggs, depends on the variable size of the parent, and on the degree 

 of m9,turity of the eggs. In the other two species, on the co^ntrary, 

 the ovipositor is perfectly smooth, and we find that the eggs are in- 

 serted. Those of concavum are 0.25-0.30 inch long, very 

 fiat, over thrice as long as wide, pointed at each end, with 

 the edges beveled off or emarginate (Fig. 59, a side view, 

 h front view, enlarged, c, d natural size). They are of a dark 

 slate-color, and are thrust into crevices and into the softer 

 ^& parts of bark or of stems. The lower or first inserted end is 

 protected by a dark, adhesive substance, which hardens and 

 sometimes extends the whole length of one of the borders ; 

 and several eggs are usually pressed close to each other. 

 Those of Gurvicauda are deftly inserted between the upper 

 and lower epidermis, and along the edges of different leaves — those 

 of oak being seemingly preferred. They are inserted contiguously, 

 but not overlapping, and, though of about the same form as those of 

 ollongifolia, are at first so much thinner as scarcely to cause any 

 swelling of the leaf. 



All these eggs swell or increase in thickness as they approach 

 the hatching period. We may explain this fact on the principle of 

 ■endosmosis with those which are imbedded in living plant tissue; but 

 it is my experience that the wood oi'pith around such eggs is very 

 generally deadened, and even if such an explanation were sufficient 

 with the softer, imbedded eggs, it would not answer with the harder 



