546 I'ROVEIUHNa^ OF THE NATfOXAL MVHEUM. vol. xxxvi. 



the anterior, middle, and posterior tergal plates {Tergalplatte?i) , 

 resi^ectively ; the second, articulating with the pleural wing process, 

 is the middle hinge plate {M ittlegelenkplatte) ; Avhile the third is 

 named the iiostcrior anal hinge plate [Analgelenkplatte) . 



Berlese (lOOO) in treating of the wing articulation, as in his treat- 

 ment of the thorax, attempts to line up the parts in four consecutive 

 series corresponding with the division of the tergum. In order to 

 make his scheme consistent, he calls the hairy pad representing the 

 tegula, on the front edge of the wing base, the acroptero. The first 

 and second axillaries. though figured as perfectly distinct, are in- 

 cluded under the name proptero. the third is the mesopfero^ Avhile 

 the name laetaptcro is given to a rare sclerite in the axillary mem- 

 brane which does not correspond with the fourth sclerite of Orthop- 

 tera and IlA'menoptera. The latter Berlese identifies in Acridlum as 

 the " mesoptero," although a sclerite is present in AcrkUum which in 

 every way corresponds with his " mesoptero '' of other orders. 



The writer retains in the present paper the general term of axil- 

 laries used by Straus-Diirckheim. and designates the uulividual 

 sclerites as the fnt^ second^ tliird^ and fourtli^ though, as already 

 pointed out, this enumeration does not correspond with that of Straus- 

 Diirckheim. (For synonymy see (Glossary.) 



Tt will not be necessary to describe in detail the axillary parts 

 in each order. They can be sufficiently made out by a study of plates 

 47, 48, 04-09, and a comparison with text figs. 1 and 5 will show 

 the general plan which prevails. The four principal axillaries are 

 indicated by the numerals 1, 2, 3, and. 4; b}' the abbreviations 

 1 Ax^ 2 Ax^ 3 Ax^ and 4 Ax; or by shading in transverse lines for 

 the first and fourth, in oblique lines for the second, and in longi- 

 tudinal lines for the third. The median i)lates are indicated by 

 broken oblique lines. The articulation of the sclerites to the notum 

 is shown in figs. 75, 90, 90, 127, 128, 129, 131, 130, 150, and Kil, and 

 b}^ text figs. 1 and 0. 



The wing base is a difficult subject to illustrate because the small 

 sclerites are so easily turned in slightly different positions and then 

 present very different appearances. Most of the drawings have been 

 made by getting first a camera lucida sketch of the specimen mounted 

 in water or glycerine and flattened out under a cover glass, and then 

 drawing in the details from dissections and a closer examination 

 under a binocular microscope. But perhaps a dozen different draw- 

 ings could be made from the same specimen all differing in details. 

 The following are general descriptions of the specific characters of 

 the various elements of the wing base. 



The fegida (Tr/). — This is usually a membranous or semichitinous 

 pad-like lobe developed on the anterior membranous part of the wing 

 root near the base of the costal vein. It is nearly always made con- 



