20 SCUDDEE ON THE DEVONIAN 



when first calling attention to this fossil, the distinctive features of two tolerably well sep- 

 arated groups combined in one individual : certain features of the wing are distinctively 

 Sialid in character ; others occur nowhere but in the Odonata. Yet these two groups 

 belong, one to the Neuroptera proper, the other to the Pseudoneuroptera, and we find 

 here the earliest proof of their common origin, in a wing whose type is more distinctly 

 synthetic than any other known. It seems also to bring new and unanticipated evi- 

 dence in support of my view of the homologies of the vein arising from the arculus in 

 Odonata. 



It is plainly impossible for us to place this insect in any known family of Neuroptera. 

 It must be considered the first known member of a family, forming the connecting hnk 

 between the Neuroptera proper and Pseudoneuroptera, and will be evidence, in so far as 

 it goes, of a closer connection between these two groups, than between the latter and Or- 

 thoptera. For this family I would propose the name of Homothetidae, and would char- 

 acterize it as a family of Neuroptera {sensu latiori), alhed to Sialina, but in which the prin- 

 cipal scapular branch, instead of originating as in Sialina directly from the main stem, 

 usually near the middle of the wing, arises in common with or close beside the externo- 

 median vein, from an arculus near the base of the wing, connecting the scapular and inter- 

 nomedian veins ; and in which, further, the basal and apical offshoots from this main 

 scapular stem are differentiated, instead of exhibiting a similar and uniform character. 



This insect was found in plant bed No. 8, of Professor Hartt's section, the highest in 

 the series as developed at the Lancaster locality. 



VI. Dtscritus vetustus. pi. 1, fig. 4. 



Dyscritus vetustus Scxjdd., Geol. mag., v, 172, 176 (1868).' 



Mentioned without name, as probably identical Avith one of the other species, in my 

 letter to Professor Hartt : On the devonian insects of New Brunswick, p. 1 ; Bailey, Obs. 

 geol. south. New Br., 140; Amer. journ. sc, (2) xxxix, 357 ; Can. nat. geol., (n. s.)ii, 

 234; Trans, ent soc. Lond., (3) i, 117 — all in 1865. 



The insect briefly mentioned hitherto under this name has not before been figured, and 

 is the least important of the devonian wings. It consists of only a small fragment of a wing, 

 which shows a bit of the lower margin with three or four curved veins running toward it, 

 and connected rather uniformly with one another by cross veins forming quadrate cells. It is 

 plainly distinct from all the others, for the equivalent region in no case is similarly broken. 

 In Lithentomum Harttii the corresponding region is indeed not preserved, but the cross 

 veins in the neighboring parts, although weak, straight and direct as here, are so very 

 infrequent and irregular that we cannot presume the parts which are wanting below them 

 to be very different. 



The veins preserved are four in number. The uppermost has two inferior branches 

 at short distances, of which only the extreme base of the outer is preserved, while the 

 inner is traceal)le throughout its extent; It parts from the main vein, which in the brief 

 portion preserved runs nearly parallel to the lower margin, at an ordinary angle and 

 passes in a regular arcuate downward course to the margin. The three veins below this 

 take a course sub-parallel to this, and are sub-equidistant ; the upper, at the base of the 



