. An account of the alcyonarians collected by the Royal Indian marine survey ship Investigator in the Indian Ocean. Alcyonaria. 38. Fig. 22. D. andersoni. Dendronephthya andersoni, Henderson. To tliis species is referred a colony which measures 8 cm. in height and about 5 cm. in greatest breadth. The stalk measures about 2'5 cm. in length and is greatly collapsed owing to the large size of the canals and the thin walls between them. It is granular in appearance, but just at its junction with the stem it be- comes stringy. The polyparium is loose, of no fixed shape owing to the irregular length
. An account of the alcyonarians collected by the Royal Indian marine survey ship Investigator in the Indian Ocean. Alcyonaria. 38. Fig. 22. D. andersoni. Dendronephthya andersoni, Henderson. To tliis species is referred a colony which measures 8 cm. in height and about 5 cm. in greatest breadth. The stalk measures about 2'5 cm. in length and is greatly collapsed owing to the large size of the canals and the thin walls between them. It is granular in appearance, but just at its junction with the stem it be- comes stringy. The polyparium is loose, of no fixed shape owing to the irregular lengths of the branches, and is developed in one plane. The main stem gives off near its base two branches on opposite sides in the same plane, and then rises without any further branching to the tip where it divides into two. One of the lower branches is much larger than the other, thus giving a lop-sided development to the poly- parium. Two of the lower branches are flattened, reflexed, leaf-like structures which almost surround the stem, leaving only two small free spaces between their edges, below one of which arises a small branch vvith cylindrical lower portion and flattened concave upper por- tion, and directly above each open space there is a small flattened branch. The polyps are arranged in groups of three to seven, and on the edges of the flattened branches they occur singly or in small groups. They are low, oval, measuring about 0 48 mm. in height and 0 8 mm. in breadth, and placed on the stalk (about 1 mm. long) at an obtuse angle. The spicules are arranged in eight double rows in each of which there are four to five pairs of converging spicules ; the uppermost pair in each row are much longer than the others and project for a long distance beyond the polyp. The lower polyp-spicules average about 0-24 mm., the upper about 0"8 mm. in length and project for 048 mm. beyond the polyp. On the aboral surface of each tentacle there are two rows of small flat rod-like spicu
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Keywords: ., bookauthorthomsonjarthurjohnart, bookcentury1900, bookdecade1900
