Cactus, or plural "cacti" show many adaptations to conserve water. Most species of cacti have lost true leaves, retaining only spines, which are highly modified leaves. Succulent plants, also known as succulents or sometimes fat plants are plants having some parts that are more than normally thickened and fleshy, usually to retain water in arid climates or soil conditions. Strong high-quality puzzle pieces. Made from recycled board and printed with vegetable based ink. This superior quality puzzle will delight and educate all at the same time.