The Devonian Insects of New Brusnwick. 

 By Samuel H. Scudder. 



CONTENTS. 



I. Introduction. VIII. Xcnoneura antiquorum. 



II. Tlie structure of the wings in Ejihemeiidae ; IX. General summary. 



with a note on a Jurassic may-Hy. X. Note on tlie geoh)gic:il relations of the fossil 



III. Platephemera .antiqua. insects from the ilevonian of New Briins- 



IV. Gerephemera simplex. wick. By Principal J. W. Dawsok, LL.D., 

 V. Homothetus fossilis. F. R. S., etc. 



VI. Dyscritus vetustus. XI. Explanation of the plate. 



VII. Lithentomum Harttii. 



1. Introduction. 



Investigation of fossU remains of the oldest insects Is nearly always extremely diffi- 

 cult and j^erplexing, and often very unsatisfactory in its results. The interest, however, 

 necessarily attaching to the beginnings of life, warrants any labor that may be expended 

 upon them. Especially is this true of the fragments treated of in this paper, because 

 they are as yet the only insect remains which have been found in rocks older than 

 the carboniferous formation in any part of the world. The writer may be pardoned for 

 adding that they possess a special attraction for him, as among the specimens which 

 first directed his particular attention to fossil insects, and he only regrets that so 

 long a period as fifteen years should have elapsed before their full discussion. 



The remains consist entirely of broken wings, and were discovered in 1862, by the 

 late Professor C. F. Hartt (at the time of his death director of the geological survey 

 of Brazil), while searching for plant remains in the devonian shales near St. John, 

 New Brunswick. The locality — called Fern Ledges by Mr. Hartt, from the abundance 

 of plant remains which occur in the black shales that are interstratified with the 

 prevailing sandstones — is about a mile west of the town of Carleton, not far 

 from St. John. The rocks form a series of ledges, exposed on the sea-shore between 

 high and low water marks. The beds of sandstone and shale, of which they are 

 composed, have a seaward dip of about 45°, and a strike of about W. 10° N., 

 corresponding very nearly to the trend of the shore. The fossiliferous shales between 

 the enclosing sandstones are worn away by the action of the water, leaving the fossils 

 accessible in only a few places. The whole deposit is of very limited extent ; it 

 reaches along the shore for about three hundred and twenty-five paces, exposing a thickness 

 of strata of about forty-five meters, with a width of about ninety meters. 



