264 ORISMOLOGY. 
25. Ruomsoip (Rhomboidea). Quadrilateral -with the 
sides equal, but with two opposite angles acute, and 
two obtuse. Pirate X XVII. Fie. 62. 2”. 
96. Trapezate (Trapezata). Quadrilateral with the 
four sides unequal, and none of them perfectly pa- 
rallel. Prate XIV. Fre. 4. 
27. Trapezor (Trapezoidea). Quadrilateral, with two 
sides unequal and parallel?. Pirate XXVI. 
Fie. 34. bi. 
28. PARALLELOGRAMIcAL (Parallelogramica). Qua- 
drilateral, with add the angles right angles, and all 
the sides parallel, but two longer than the others. 
VI. FORM®. 
1. SpHerticaL (Spherica). The shape of a globe. A body 
whose diameter every way is equal. Pirate XX. 
lees a 
2. OrsicuLaTE (Orbiculata). A depressed globe, 
whose horizontal section is circular, and vertical 
Oval eet A Re DOG sere Ooi 
3. Lenticuuar (Lenticularis). Lens-shaped. Whose 
horizontal section is circular, and vertical lanceo- 
late. Ex. Abdomen of Cynips aptera. 
4, OvaLirorM (Ovalzformis). Whose longitudinal sec- 
tion is oval, and transverse circular. Prare XX. 
Fia. 6. ° 
5. Exxipsorp (Lllzpsocdea). Whose longitudinal sec- 
* ‘We have departed from the more usual definition of trapezoid, 
‘* An irregular figure whose four sides are not parallel,” because the 
above is best suited to forms in insects. 
> We use this term to denote the shape of solid bodies. 
