ko.l33i. DRAGON-FLY WING VENATION— NEEDHAM. 761 



(c) In the study of fossils, that are oftener fragmentaiy than other- 

 wise and that present no other characters so well preserved. From 

 the standpoint of pure science, the need of better knowledge is greatest 

 'here. The present systematic arrangement of the known fossil Odo- 

 nata is a miserable jumble, and some statements that have been drawn 

 from it in a number of l)ooks and papers on geographic distribution 

 !are quite misleading. Instances have already been cited of fossil 

 'forms that are referred to the wrong suborder. There have been some 

 greater and manv lesser unnecessarv errors of reference. LiheUuUum 

 \lcaupii Westwood is probably not a dragonfly at all, while Heniei^o- 

 loides gigantens Buckman is a dragonfly of the subfamily hopldehinse, 

 (as may be seen by comparing Buckman's figure with the f orewing of 

 'fig. 31), and not a huge hemerobian, as has been supposed. Lihellu- 

 liuiii agrias Westwood belongs in the ^Eschnidfe, being in every detail 

 that Westwood figured diametrically opposed to Libellulida?. Lihel- 

 \lMlium antiquum Brodie belongs in the ^I^schnidiina^, and so also does 

 [ the ^Eschna fmdersiensis Woodward. The only fossil ^Eschna that 

 I seems to fit that name in the modern sense of it is ^K soUda Scudder. 

 : ^schna separata Scudder and jEsclina metis Heer, especially the latter, 

 ■ which was improperly removed to Ayiax by Hagen, will go in lloplo- 

 na^schna. ^Eschna perainpla Brodie and ^Eschna hageni Heer, judged 

 'I by poor figures, will hardly go in the iEschninie. Stenogompkus car- 

 ' Moni Scudder," which was independently determined by the two most 

 ' distinguished students of the Odonata, de Selys and Hagen, to be 

 nearest Gomphoides stigmatus (Plate XXXIII, fig. 2) among living 

 forms, and which stands as the only known American fossil Gomphine, 

 is in fact a Libellulid in every line, and had the hind wing been pre- 

 served no one would have thought it a Gomphine. 



While it would be manifestly impossible, owing to defective preser- 

 vation, to refer fossils, in most cases, to genera of such thin cleavage 

 as modern practice allows for recent species, it is very obvious that 

 a new study of the types of the older authors would help much toward 

 a better arrangement of our system. New figures of these are espe- 

 cially needed. Mr. Scudder\s figures are the only ones that I have 

 found entirely reliable. All others show omissions or alterations of 

 unnoticed characters of critical importance. For instance, the oblique 

 vein, even in Hagen's drawings, is rarely shown. This is not surpris- 

 ing, so long as it was regarded merely as one of a row of cross veins; 

 buT it is disconcerting in a study made from the ontogenetic stand- 

 point. When the structural characters that are actually preserved ])y 

 fossils alreadv in collections have been fully interpreted, we shall 

 know much more concerning the history of the group. Generalisa- 

 tions can not safely proceed faster than the development of real 



knowledge. 



"Bull. 93, U. S. Geol. Surv., pp. 12-15, pi. i, % 1- 



