Whatever the case, the shape of the cross-section of the said sphenoidpart is either of an isosceles spherical trapezium or of any spherical quadrilateral.
无论哪种情况，楔形体的横截面形状要么是有两条边相同的球形四边形，要么是任意球形四边形。
2
Their conical sphenoidpart, for the configuration of which at least four conical surfaces are used, can have the same cross section all over its length or different cross-section per parts.