The encyclopædia britannica; a dictionary of arts, sciences, literature and general information . tellum of the mesothorax being often especially each segment of the thorax has a slertium with which amedian presternum and paired cpisterna and epimera are oftenassociated (see figs. 3. 4). The recent suggestion of K. \V. Verhoeff(1904) that the hexapodan thorax in reality contains six primitivesegments is entirely without embryological support. Legs.—Each segment of the thorax carries a pair of legs. Inmost insects the leg is built up of nine segments: (l) a broadtriangula
The encyclopædia britannica; a dictionary of arts, sciences, literature and general information . tellum of the mesothorax being often especially each segment of the thorax has a slertium with which amedian presternum and paired cpisterna and epimera are oftenassociated (see figs. 3. 4). The recent suggestion of K. \V. Verhoeff(1904) that the hexapodan thorax in reality contains six primitivesegments is entirely without embryological support. Legs.—Each segment of the thorax carries a pair of legs. Inmost insects the leg is built up of nine segments: (l) a broadtriangular, sub-globular, conical or cylindrical haunch {coxa); {2)a smM trochanter: (3) an elongate stout thigh (/V-mur); (4) a moreslender shin (/i6iVi); and (5-9) a foot consisting of^fivc tarsal fifth (distal) tarsal segment carries a median adhesive pad—the pulviUu*—on either side of which is a claw. The pulvillus is 4-20 HEXAPODA [CHARACTERS probably to be regarded as a true terminal (tenth) segment of the leg,while the claws are highly modified bristles. Numerous bristles are. Afttr Mulatt, Ent. Bui!. 3, n. s. ( DqjL Agr.). Fig. 3.—Thorax of Saw-Fly (Pachynemalus). I, Dorsal view. d, Pronotum, II, Ventral view. Mesothorax: III, Lateral view. e, Prescutum. IV, Lateral view with /, Scutum,segments separated, g, Scutellum. Prothorax: A, Post-scutellum. a. Episternum. i, Mesophragma. b. Sternum. j, Epimeron. c. Coxa of fore-leg. k, present on the thighs, shins and feet of insects, some of them•o delicate as to be termed hairs others so stout and hard that /, Coxa of middle leg. Metathorax:»t. , Coxa of hind , First Abdominal Segment,t, Tegula at base of fore-wing.
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectencyclo, bookyear1910
