Archive image from page 14 of A handbook of British lepidoptera. A handbook of British lepidoptera CUbiodiversity1126142 Year: 1895 ( INTRODUCTION monly represented by a group of stiff scales. When there is no frenulum, the costal area of the hindwing is generally dilated basally, so as to rest more firmly against the forewing, and avoid dislocation. Hut in the Microptcri/gitia (as recently discovered by Professor Comstock) a different system prevails; a membranous or spine-like process called the jugvm rises from the dorsum of the forewing near the base, and passes underneath the hindwing, w
Archive image from page 14 of A handbook of British lepidoptera. A handbook of British lepidoptera CUbiodiversity1126142 Year: 1895 ( INTRODUCTION monly represented by a group of stiff scales. When there is no frenulum, the costal area of the hindwing is generally dilated basally, so as to rest more firmly against the forewing, and avoid dislocation. Hut in the Microptcri/gitia (as recently discovered by Professor Comstock) a different system prevails; a membranous or spine-like process called the jugvm rises from the dorsum of the forewing near the base, and passes underneath the hindwing, which is thus held between the process and the overlapping portion of the forewing. The wings are traversed by a system of veins, tubular structures which serve at once as extensions of the tracheal system, and to form a stiff framework for the support of the wing. In the normal type of /,</,;,/,,/,/rni. the I'orewings possess three free veins towards the dor- sum, termed la, lb, and lc; a central cell out of which rise ten veins, numbered 2 to 11, the sides of the cell being known as the upper median, lower median, and transverse veins respectively ; and a free subcostal vein, numbered 12: whilst the hindwings differ from the forcwings in having only six veins rising from the central cell, numbered 2 to 7, so that the \'vvr subcostal vein is numbered 8. In some forms a forked parting- vein traverses the middle of the cell longitudinally, and a second parting-vein traverses the upper portion, so as to form a secondary cell; but these arc more frequently absent or represented only by folds in the membrane. In a few forms there is a tendency to the production of several False veins, termed psciidoneurid, appearing as short- branches from the subcostal vein of the hindwings to the costa ; these are thickenings of the membrane, and arc commonly very irregular and variable, often uneven in thickness or incomplete. Some- times one of these near the base is better developed and more
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Keywords: 1890, 1895, archive, book, bookauthor, bookdecade, bookpublisher, booksubject, bookyear, drawing, historical, history, illustration, image, lepidoptera, london_new_york_maomillan, meyrick_edward_1854_1938, page, picture, print, reference, vintage
