The abdomen is full of oil, and is much prized as a delicacy by the natives, who tell many strange legends about the creature, but the philosopher may well find its structure more strange than fiction, and the consideration of its morphology an intellectual feast. The appearance of the thorax and of the thoracic limbs is thoroughly Pagurid; the structure of the abdomen is highly peculiar. From the ventral surface (Fig. 119) we can see at the tip of the tail three small calcified plates, which represent the fifth and sixth terga and the telson. Attached to the sixth segment are the much reduced and rudimentary pleopods of that segment, and on the left hand side of the body in the female are three well-developed pleopods of the first, second, and third segments, which are used for carrying the eggs. The extraordinary asymmetry of these limbs compared with the complete symmetry of the abdomen itself is only explicable on the hypothesis that these animals are descended from Hermit-crabs which had lost the pleopods on the right side. [Illustration: FIG. 119.—_Birgus latro_, ♀, × ⅙, ventral view. _Ab_, First pleopod; _T_, last pereiopod. ] These appendages are entirely absent in the male. The ventral surface of the abdomen is curiously warty and rugose, and is very soft and pulpy owing to the immense store of oil which it contains. [Illustration: FIG. 120.—Dorsal view of abdomen, =A=, of _Cenobita_, sp.; =B=, of _Birgus latro_. _T_, Telson; 1–6, 1st–6th abdominal segments. ]