266 ORISMOLOGY. 
creasing in diameter from the base to the apex, and 
propagated in a curved line. 
16. Cuirriror (Cultriformis). Whose horizontal sec- 
tions are equal acute-angled triangles, or a three- 
sided body with two equal sides large and the 
third small. 
17. Detroip (Deltoidea). Short with the horizontal 
section triangular and decreasing in diameter to- 
wards the base. Ex. Apex of the posterior tibia 
in Copris lunaris. 
18. TrigonaL; TrerraconaL; PenraconaL; Hrxa- 
GONAL; PoLtyGonaL (Trigona; Tetragona; Pen- 
tagona: Fexagona; Polygona). Whose horizon- 
tal section is triangular; quadrangular; quin- 
quangular ; sexangular; multiangular. 
19. TrrepRAL; TETRAEDRAL; PENTAEDRAL; HExa- 
EDRAL; PotyEeDRAL (TZriedra; Tetraedra; Pen- 
taedra; Flexaedra; Polyedra). ‘That hath three 
sides ; four sides; five sides ; szx sides ; many sides. 
20. PrismorpaL (Prismozdalis). Having more than 
Sour sides and whose horizontal section is a poly- 
gon. Prater VI. Fie. 13. a, 6, d’. 
21. Traprezirorm (Trapeziformis). Whose horizontal 
section is a Trapezium. 
22. ‘TRAPEZOIDIFORM (Tyapezoidiformis). Whose hor7- 
zontal section is trapezoid. 
23. RHOMBIFORM (Rhombiformis). Whose horizontal 
section is rhomboidal. Prare VIII. Fie. 11. 
* The word employed in Botany to denote a Polygon is prismati- 
cal ; but since, properly defined, this term is synonymous with trique- 
trous, we thought it best to use an adjective derived from prismoid, 
which implies a body that approaches to prismatical. 
