SCUDDER ON TERTIAEY INSECTS. 537 



breadth of same 5.o«»m; length of thorax 5™™, of pedicel of wing 

 5™™, of abdomen (probably 1™™ should be added for a break at the 

 base) 39™^; length of segments 8-10, 6"^^; breadth of ninth segment 

 2.75mm^ of fifth segment 2.1™™; estimated length of whole body 55™™. 



Corydalites fecundum. — Under this name I propose to class an insect 

 which laid some remarkable egg-masses, obtained in numbers by Dr. O. 

 A. White, at Crow Creek, fifteen miles northeast of Greeley, Colo., in 

 lignitic beds of the Laramie Group. These egg-masses are five centi- 

 meters in length by nearly two in breadth and one in height, nearly 

 equal throughout, rounded and slightly pointed at the tip, and of a dirty 

 yellowish-brown. They contain each about two thousand eggs, definitely 

 arranged, and coated with a covering of what was presumably albu- 

 minous matter, which also surrounds each egg. The close general re- 

 semblance of these eggs and of their clustering to that of the eggs recently 

 referred by Mr. C. Y. Eiley to the neuropterous genus Corydalus* leave 

 little doubt concerning their probable affinities. Mr. Eiley's description 

 is as follows : — 



" The egg-mass of Corydalus cornutus is either broadly oval, circular, 

 or (more exceptionally), even pyriform in circumference, flat on the at- 

 tached side, and plano-convex [broadly convex is doubtless meant] on 

 the exposed side. It averages 21"" in length, and is covered with a 

 white or cream colored albuminous secretion, which is generally splashed 

 around the mass on the leaf or other object of attachment. It contains 

 from two to three thousand eggs, each of which is l.S""'" long and about 

 one-third as wide [he figures them of a slenderer form] ■ ellipsoidal, trans- 

 lucent, sordid white, with a delicate shell, and surrounded and separated 

 from the adjoining eggs by a thin layer of the same white albuminous 

 material which covers the whole. The outer layer forms a compact arch, 

 with the anterior ends pointing inwards, and the posterior ends showing 

 like faint dots through the white covering. Those of the marginal 

 row lie flat on the attached surface ; the others gradually diverge out- 

 wardly, so that the central ones are at right angles with said object. 

 Beneath this vaulted layer the rest lie on a plane with the leaf, those 

 touching it in concentric rows, the rest packed in irregularly."} 



In the fossil ootheca the mass is much larger and more elongated, and 

 possesses besides one characteristic in which it differs strikingly from 

 that of Corydalus (and on which account, particularly, I have used a new 

 generic appellation), viz : the division of its mass into two longitudinal 

 and equal halves by an albuminous wall, or rather by double albuminous 

 walls, which may be parted above, leaving as the only connection between 

 the two halves their common albuminous floor. There are indeed a few 

 specimens which show no sign of this division, but a median furrow, or a 



* It has been suggested that these may belong rather to Chauliodes, a closely allied 

 genus of Neurojytera; but Mr. Eiley declares that they are identical with those found 

 in the body of Corydalus. 

 . t Proc. Amer. Assoc. Ad. Sc. xxv, 277-278. 

 Bull. iv. Ko. 2 15 



