NO. 1923. DESCRIPTIONS OF PACIFIC ALCYON ARIA— NUTTING. 47 



Genus ANTHOPTILUM Kolliker. 



Polyps large, disposed in numerous short rows. Rachis without a 

 streak of undeveloped polyps below the developed ones. Zooids may 

 be on all sides of the rachis. Spicules, if present, confined to the 

 proximal end of stalk. 



ANTHOPTILUM MURRAYI Kolliker. 



Anthoptilum murrayi Kolliker, Challenger Reports, the Pennatulida, 1880, p. 14. 



The colony is 44 cm. in length, of which the stalk is 5.1 cm. The 

 stem has a distinct enlargement just below the rachis and diminishes 

 gradually in size to the end bulb, the two being almost of the same size 

 and insensibly blending into each other. The diameter of the swell- 

 ing is 8 mm. and of the end bulb 5.5 mm. The narrowest part of the 

 stem is between the two and is 4.5 mm. broad. The swelling has a 

 series of very evident wrinkles or longitudinal furrows. 



The polyp bodies are tubular, transversely wrinkled or corrugated, 

 6 mm. high to the bases of the tentacles, 2 mm. in diameter at the 

 middle, diminishing slightly in diameter at each end. The tentacles 

 are 5 mm. long, not longer than body in specimens studied. The pin- 

 nules are numerous. The polyps are very irregularl}'^ distributed, 

 perhaps an average distance between them is 5 mm. They can 

 hardly be said to be arranged in transverse rows, the midline, ven- 

 trally, being occasionally invaded by polyps, though in general it is 

 free. On the proximal part of the rachis the polyps are scattered 

 singly or in pairs; on the distal portion they are more crowded and 

 generally occur in pairs or in short oblique rows of three. At the 

 distal end they are crowded into a dense tuft, in the larger and older 

 specunens, and their arrangement is hard to ascertain, the lateral 

 and ventral surfaces of the rachis being entirely covered with pol3^s. 



The ventral midline is covered, and the mass of polyps is as dense 

 as in A. thoinsoni Kolliker. The bases of the polyps in a given line 

 are often slightly coherent, 



Zooids: These are small and numerous, and are scattered over 

 pretty much the whole surface of the rachis, except the ventral region, 

 which is not occupied by a furrow and is rarely invaded by zooids. 

 There is a narrow dorsal band", sometimes depressed, which is usually 

 free from zooids but is occasionally invaded. The zooids are unevenly 

 distributed, sometimes forming patches or lines, and at others scat- 

 tered haphazard. They are all small. 



The spicules are absent. While there are a few calcareous particles 

 on the end bulbs, I am not sure that they are not adventitious. 



Color: The upper part of the stem, the rachis, and lower parts of 

 the pol3rps are pale yellowish, with a reddish-brown tinge. The upper 

 parts of the polyps and the tentacles are warm reddish-brown, the 



