22 Bolton, '' Mark Stin-np " CoLlcctioji of Fossil Insects. 



Left tegiiicn. — The sub-costal vein is widely separated 

 from the costal margin, and runs parallel to it along almost 

 the whole of its length, its final twigs bending outwards and 

 reaching the costal margin at a point near the beginning of 

 the distal fourth of the wing's length. A considerable number 

 of twigs are given off to the costal margin, the proximal ones 

 being simple, whilst those in the middle and most distal por- 

 tion are one, and in some instances thrice branched. The gene- 

 ral form of the sub-costal is strap-shaped, a typical archimy- 

 lacrid feature, whilst the multiple division of the distal twigs 

 is suggestive of Necymylacris. 



The radius is undivided for the first fourth of its length, 

 and then gives origin to the radial sector, beyond v^-hich it 

 divides into two twigs, the outer of which forks just before 

 reaching the outer margin, and the inner forks twice, ending 

 upon the margin in three divisions. This portion of the radius 

 takes but a small share in the wing apex. 



The radial sector passes to the outer half of the wing tip, 

 forking three times during its course; two of the secondary 

 twigs and two of the tertiary twigs also fork, so that this divi- 

 sion of the radius ends u]:)on the margin in eight divisions. 



The main stem of the median vein curves inwards, and 

 gives off four branches outwardly. The first branch divides 

 intO' three twigs before reaching the wing apex, and the second 

 divides into four. The remaining branches are undivided. 

 The divisions of the median occupy the inner half of the wing 

 apex. The main branch of the cubitus follows a parallel course 

 to that of the median, giving off" inwardlv a series of 8 — lo 

 twigs, of which the first, fourth, seventh and eighth again sub- 

 divide. These divisions occupy the whole of the inner margin 

 of the wing, outside the anal area. The anal area is best 

 described as an oval, bluntly pointed at both ends. It is 

 crossed by ten veins, one only of which is forked 1<jw down 

 against the wing margin. 



Right tcgmen. — The right wing presents only minor differ- 

 ences. The sub-costal vein is not nearly so well developed as 

 in the right. The sub-divisions of the radius and radial sector 

 are sixteen in number against thirteen in the left wing, and 

 the median has seven divisions as against ten in the right wing. 

 The cubitus of the right wing is somewhat more developed 

 than in the left, taking a distinct share in the wing apex. 



The anal area has been destroyed, two small traces only 

 being left of the first pair of veins. The intercalary venation 

 appears to consist of a fine meshwork, but this, is by no means 

 clear; certainly there is no trace of straight cross veins. 



Affinities. — The beautiful condition of preservation of these 

 wings renders generic determination less difficult than usual. 

 The following assemblage of characters is at once characteris- 

 tic of these wings, and also of the genus Vhylloblatta. Wings 



