ANATOMY OF MARELLIA REMIPES — CARBONELL 89 



meet opposite the frontal surface to form the strongly arched dorsal 

 wall, which shows a sinuous crest along its midline (see C). 



The basal or upper surface of the egg pod (g) which adheres to 

 the leaf (Lf) is always irregular in outline. It invariably shows a flat 

 lobe that extends backward from the dorsal part of the ootheca 

 (shown in fig. 18 A, E). The adherence of this basal surface to the 

 leaf is remarkable, and when it is forcibly taken from the leaf it 

 usually carries a piece of the leaf epidermis with it. 



The inferior part of the frontal or opercular surface shows a pe- 

 culiar disposition. There are on it two slender, lateral frontal proc- 

 esses (A, B, j, i) which prolong the raised lateral edges of the oper- 

 cular surface, and a median small, upcurved process (i) on the frontal 

 side of the apical lobe of the egg pod. The bases of these three proc- 

 esses limit a triangular, somewhat excavated area on the frontal sur- 

 face of the apical lobe of the ootheca. 



As can be observed by sectioning the egg pod (E, F), the eggs 

 occupy only the upper or basal two-thirds of it. They are always 

 arranged in four vertical rows, usually of six or seven eggs each, 

 making on the average a total of 23 to 25 eggs. Occasionally an un- 

 usually large pod with a greater number of eggs can be found. The 

 eggs are embedded in the usual hardened frothy secretion which com- 

 pletely envelops them. The apical or inferior third of the egg pod, 

 which contains no eggs (F), is entirely formed of this hardened 

 secretion. 



Inside the egg pod, the eggs lie in a horizontal position. The 

 cephalic end of the embryo is always directed toward the frontal or 

 opercular surface. The egg pods are always located near the edges of 

 the leaves, with the frontal or opercular surface directed outward, 

 i.e., toward the edge of the leaf. As we shall see below, this fact must 

 be related to the way in which the egg pod is laid. 



Though the actual oviposition has not been witnessed by the writer, 

 he has advanced a tentative explanation of the way in which it may 

 be done (Carboncll, 1957). The anatomy of the female abdomen and 

 the structure of the ovipositor have suggested to him the following 

 mode of oviposition: the ovipositing female, sitting near the edge of 

 the upper surface of a floating leaf, with her abdomen pointing out- 

 ward, retrocedes and submerges its tip, reaching the inferior surface 

 of a nearby leaf. Then the emission of the frothy cemental secretion 

 begins, perhaps preceded by a scratching of the underside of the leaf 

 by the upper valvulae of the ovipositor. After the preparation in this 

 way of the flat foundation of the egg pod, its construction proceeds by 



