. An account of the alcyonarians collected by the Royal Indian marine survey ship Investigator in the Indian Ocean. Alcyonaria. 57. Fig. 30. D. crystallina. The stalk is short, and the long axis of the polyp-bearing portion stands at an angle to the stalk. The stalk is short, measuring 1'2 cm. in length, somewhat thick and rigid, and gives off fi'om its base and for a short distance up the side numerous stolons to which are attached frag- ments of shells and grains of sand. The polyparium is pear-shaped and slightly flattened in one plane, and consists of a number of branches which rise almost
. An account of the alcyonarians collected by the Royal Indian marine survey ship Investigator in the Indian Ocean. Alcyonaria. 57. Fig. 30. D. crystallina. The stalk is short, and the long axis of the polyp-bearing portion stands at an angle to the stalk. The stalk is short, measuring 1'2 cm. in length, somewhat thick and rigid, and gives off fi'om its base and for a short distance up the side numerous stolons to which are attached frag- ments of shells and grains of sand. The polyparium is pear-shaped and slightly flattened in one plane, and consists of a number of branches which rise almost at a right angle to the stem. The stem rises for a short dis- tance entire, and then gives off a large branch on each side in the plane of flattening. Slightly farther up it gives off a second large branch on one side also in the plane of flattening. The larger branches rise at an angle which approaches a right angle, and give rise by repeated divisions to the small twigs which bear the polyps. Over the surface of the stem and branches smaller branches arise, which either bear the polyps themselves or give rise by division to the polyp-bearing twigs. Two of the lowest branches are leaf-like, flattened and reflexed, and almost surround the stalk, leaving two open spaces between the edges of their base of attachment, in which small ordinary branches with a rounded stem are found. The polyps are arranged in small groups of five to six, two or three of these being grouped together to form larger bundles. On the edge of the flattened, leaf-like branches the polyps occur singly or in small groups. The polyps are low, shallow, cup-shaped, measuring 0'4 mm. in height and 064 mm. in breadth. Each polyp sits at a right angle on a stalk which measures on an average 08 mm. in length. The polyi)-spicules are arranged in eight double rows, in each of which there are five pairs of converging spicules. The upper pair in each row projects for a short distance beyond the polyp, and in the space
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