178 S. H. SCUDDER ON THE WINGS OF SOME FOSSIL NEUKOPTERA 



the lower branch diverges rather widely from it, the space between being divided into 

 equal distances by several independent veins. The v. interno-mcdia starts from the same 

 point as the former, and is simple. The v. analis is widely separated at the base from the 

 previous, is much curved, first upwards and then downwards, and sends out several branches 

 which curve as they are directed towards the margin. The veins and their branches are 

 traversed everywhere by rather frequent cross-veins, but the wing is nowhere reticulated 

 except slightly around the margin. 



Hind Wing. Either the v. mediastina or scapularis is wanting, very probably the latter, as 

 the area extemo-media is very wide. The branching of the v. extemo-media is nearer the base 

 than in the fore wing ; the v. interno-mcdia is apparently wanting, and the v. analis is more 

 uniformly curved. 



Odonata. 



Quite a characteristic feature of this group is that the v. marginalia extends but half way 

 along the margin, and terminates abruptly ; and that the v. mediastina runs nearly parallel to 

 it, with a distinct space between them ; when it reaches the point where the v. marginalis ter- 

 minates it turns abruptly upwards, forming the " nodus" and protects the rest of the margin. 

 The v. scapidaris runs parallel to the v. mediastina as far as the nodus, is there connected by 

 a strong cross-vein to the v. mediastina, and then continues on in a direct line to the tip of 

 the wing. At a short distance from the origin this vein sends clown a short abrupt branch, 

 which meets a similar branch directed upwards from the v. extemo-media ; from the cross-vein 

 thus formed, two veins take their rise ; the upper I consider to belong to the v. scapularis, 

 and to be properly a continuation of the short abrupt branch ; it continues a short distance 

 either parallel to the v. scapularis or adjacent to it (as in some Agrionina), and then branches ; 

 it generally branches twice before reaching the nodus, and once at or just beyond that point, 

 with which it is connected by a continuation of the strong cross-vein before mentioned. 1 

 The v. extemo-media runs quite directly to the margin, curving downwards more or less at 

 the outer half, and running nearly parallel to the lowest branch of the v. scapularis ; it 

 sends upwards the short abrupt branch mentioned to meet that of the v. scapularis, which 

 turns abruptly outwards at right angles again, sometimes joining the vein again a short dis- 

 tance on, sometimes continuing freely to the margin. The intricacies of the neuration 

 are such that the v. interno-mcdia can be traced definitely but a short distance, to a point 

 below the cross-vein, uniting the v. scapidaris and extemo-media; here it sometimes forks, 

 sometimes continues on single but contorted, and sometimes seems to stop altogether. 

 The v. analis is frequently if not generally confluent with the px-eceding for a short dis- 

 tance, then diverges and forms the lower border of the wing. The area marginalis, medi- 

 astina, scapularis and intcrno-media, are traversed by numerous cross-veins ; the area extemo- 

 media is free from them as far as the cross-vein ; beyond this they are present ; the spaces 

 enclosed by the branches of the v. scapularis, and all the wing below the upper branch of 

 the v. extemo-media, are reticulated. That the space between what I have here considered 

 as the lower branch of the v. scapidaris and the upper branch of the v. extemo-media, has 

 cross-veins and no reticulations, except in a few cases close to the margin (JEschnidce) is 

 one reason for my conclusion concerning the meaning of the cross-vein and its branches. 



Sialina. 

 The v. mediastina starts at considerable distance from the v. marginalis, approaching it 



1 In Lestes, however, it is somewhat different; it sends out a branch once before the nodus and once beyond. 



