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MB. H. BOLTON ON SOME INSECTS 



[vol. lxxii, 



the inner half of the intercostal area is double the width of the 

 outer half. 



The radius is a simple vein, giving off the radial sector at the 

 base, and then passing out towards the tip of the wing parallel to 

 the sub-costa, from which it remains equidistant along the whole 

 of its course. The radial sector diverges widely from the radius, 

 and now shows but one posteriorly-directed branch, which forks 

 just as the broken edge of the wing is reached. So widely does 

 the radial sector diverge from the radius, that the area included 

 between them is equal in diameter, immediately beyond the forking 

 of the radial sector, to the whole area lying between the radius 

 and the costal margin at its widest part. Allen shows that 

 two additional undivided twigs were sent off posteriorly from 

 the radial sector, beyond which is now the broken edge of the 

 wing. 



The radius and the radial sector occupied almost the whole tip 

 of the wing. 



The median vein forks at a quarter of the length of the wing 

 from the base, the outward branch again forking before the middle 

 of the wing is reached. The two twigs so produced pass backwards 

 and outwards to the inner wing-margin, keeping parallel one to the 

 other and to the innermost twig of the radial sector. The inner 

 branch of the median diverges almost in a straight line from the 

 outer branch, so that a wide area lies between them up to the point 

 at which the inner branch forks. The forking of the inner branch 

 occurs farther out than in the outer branch, and forks a second time 

 before the inner wing-margin is reached. 



The cubitus is a remarkable vein. For nearly half its length 

 it passes in a broad curve outwards and backwards towards the 

 inner wing-margin, without forking. Beginning at the middle of 

 its length, the cubitus gives off alternate twigs upon its outward 

 and inward sides, those on the inner side being much feebler 

 than those on the outer. The two outward twigs are strongly 

 developed, and sweep in a wide curve outwards and down to the 

 wing-margin. The twigs from the inner side of the cubitus are 

 five in number, and pass directly inwards to the wing-margin, 

 with the exception of the last, which seems a feeble continuation 

 of the main stem, and curves outwards like the two outer twigs ; 

 the course of the inner four twigs is therefore much shorter than 

 that of the outer twigs, while the area that they occupy on the 

 wing-margin is also much less. This is a feature entirely unlike 

 anything seen in Fouquea. 



Four anal veins are distinguishable. The inner two arise from 

 a common base ; the remaining two are distinct. This, again, is 

 unlike what is seen in Fouquea, where the anal veins branch off 

 regularly from a single stem. 



The area tying between the first anal vein and the main stem of 

 the cubitus is very wide, much wider, indeed, than any other area 

 in the wing. 



