crossvein

crossvein

[′krȯs‚vān]
(mining engineering)
A vein that intersects an older or larger vein.
References in periodicals archive ?
Wing: Length is measured from the humeral crossvein to tip, breadth at the level of the r-m crossvein.
Rs rather short (nearly as long as distance between humeral crossvein and extreme base of Rs); anal cell longer than cell bm; anal cell produced posteroapically, inner angle formed between CuA2 and A1 strongly acute with CuA2 usually distinctly curved; basal portion of M (separating basal cells) distinct.
Wing: Base black, basicosta grey-brown; costa setulose only basally on ventral surface, anterior surface with row of pectinate short spines, longest one equal to length of crossvein r-m; costal spine longer than crossvein r-m, radical node bare, calypters yellowish, lower about half length of upper one; halter brown-yellow.
Crown-face transition with dark patch medially; forewing with veins MP' and RP separate, connected by crossvein (Fig.
The following abbreviations are used below: setae: ifr--interfrontal, fr-orb--fronto-orbital, dc--dorsocentral, ad--anterodorsal, av--anteroventral, pd--posterodorsal, va--ventroapical; wing veins: R--radial veins, M--medial veins, M-M--posterior crossvein, R-M-M-M--inter-crossvein section of M12 (that is, veins are written consistently in upper case, including crossveins); other: T--abdominal tergite, S--abdominal sternite.
16- Anal cell: (0) opening in wing margin by Y r-m crossvein length; (1) opening in wing margin by 2/3 r-m crossvein length; (2) opening in wing margin by the length of r-m crossvein; (3) closed before wing margin.
7 mm (length measured from tip to humeral crossvein, width at widest level); extensively blackish stained except for paler central parts of most cells and an almost transparent narrow sub-triangular window between 1st radial and radial sector.
Wing veins: fore wing: 2A+3A--second and third anal vein, M--media, R--radius, Rs+M--radial sector and media, a--anal crossvein, 1m-cu--mediocubital crossvein, 2r-m--second radiomedial crossvein; hind wing: 1A--first anal vein.
Wing length is measured from humeral crossvein to tip, while breadth is measured at the level of the r-m crossvein.
22 times longer than wide, with sparse setae on surface, tubercles along veins, claval veins without tubercles; 2 indistinct subapical lines of cross veins; fork Sc+RP distad of fork CuA1+CuA2; r-m crossvein slightly distad of fork MA+MP; RP apically bifid, MA apically bifid, MP apically bifid; fork PCu+A1 slightly basad of centre of clavus; Sc+R and M fused at superior-outside angle of basal cell; fork MA1+MA2 distad of fork MP1+MP 2.