670 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxix. 



inferior meinher; their hrunchlets are alwa}'^ more or less strongly 

 arcuate and directed backward; iuial veins always well developed, more 

 or less branched and curved back to the inner margin; almost without 

 exception, cross veins are abundantly developed and irregularly distrib- 

 uted. Anal area neither separated by a fold nor enlarged by fanlike 

 plaitings. Pterostigamata, cross folds, and intersections of the veins, as 

 well as all other higher s})ecializations occurring in recent insects, are 

 wanting in all Palwodictyoptera. The head is moderately large, with 

 eyes distinctly developed and rather long simple antennae. Mouth 

 parts fitted for chewing. Three similar thoracic segments, the first 

 mostly with winglike pleurites. Abdomen sessile, slender, and uni- 

 forndy segmented; the sides of the segments often with persistent 

 tracheal gills or similar processes. Legs homonomous, fitted for run- 

 ning, with 3 to i tarsal joints. Eleventh segment with more or less 

 long cerci. 



The larvfe of the Paheodictyoptera were similar to the imago, and 

 developed their wings gniduall}' without resting stages; they probably 

 lived in the water as predaceous animals. 



This order is exclusively Paleozoic and includes the oldest fossil in- 

 sects at present known. This fact, taken in connection with the very 

 primitive organization, especially with the lack of all specialized 

 structures, leads me to seek in the Paheodictyoptera the ancestors of 

 all other orders of insects. 



Family DICTYONEURID.E Ilandlirsch. 



I consider the geruis Dictyoneiira Goldenberg the type of this 

 famil3\ The wings of the Dict^^oneuridte are distinguished by a very 

 irregular reticulate intercalar}^ neuration, and have feebly divided 

 principal veins. As a rule the radial sector, as well as the cubitus 

 and the media, always separate into not more than from •! to 6 

 branches. 



A group prevailing throughout the middle and upper parts of the 

 Uppo '^aj'boniferous of F^urope. 



HAPLOPHLEBIUM Scudder. 

 HAPLOPHLEBIUM BARNESII Scudder. 



IliphijiJilchiuiii Ixtrnesli Scuddek, Pror. Bostdii Sof., XI, ISdT, p. 151; (Teol. 



Mag., IV, 1867, p. 386, pi. xvii, fig. 1. 

 Dictj/oneara ]iaplo2)hlebia GohDE'SBEm;, Fautui sararp. fo88., II, 1877, j). l(i. 

 Haplophlefiiion harnem Brongni.vrt, Fauna ent. lerr. ]iriii., 1S!K'), p. .'iLM, \A. iii, 



figs. 4, 5. 



Locality. — Sydney, Cape Breton. Allegheny staged 

 This fossil has been referred b}^ Scudder to the protophasmids 

 (orthopteroid Palaeodictyoptera). 



