NO. 1928. DESCRIPTIONS OF PACIFIC A LCYON ARIA— NUTTING. 49 



Family PROTOPTILIDvE Kolliker. 



The rachis is long and slonder; polyps sessile, in a single irregular 

 series on each side; calyces present. 



Genus PROTOPTILUM Kolliker. 



Zooids on all sides of the rachis, leaving nothing but the ventral 

 line uncovered. 



PROTOPTILUM ORIENTALE, new species. 

 Plate 6, figs. 1, la. 



Colony 13.3 cm. in length; stem to first rudimentary polyp 6.3 cm., 

 ending in an ovoid, bladder-like end bulb which is longitudinally 

 striated and measures 11 mm. by 7 mm. 



The least diameter of the stem above end bulb is 2.5 mm.; median 

 diameter 3.5 mm. 



There is a row of polyps along each side of the dorsal median space, 

 about 10 polyps in each. The calyces are short, directed distally, with 

 the inner walls very short or lacking. The outer wall is 3 mm. high, 

 and with 8 regular, large, vertical corrugations ending in lobular pro- 

 jections around the margin, covered with small needle-like spicules. 

 The polyps are partly retracted, exposing but about 2.5 cm. of their 

 length. They are 2 mm. in diameter, and their bodies are covered 

 with an armature of very conspicuous spicules which are bar-shaped 

 with the ends enlarged. They lie in every direction in the body walls, 

 and average about 1 mm. in length. The tentacles are about 3.5 

 mm. long, and have their dorsal surfaces covered by triple or double 

 rows of the same spicules placed longitudinally and very conspicuous. 

 The pinnules are short and rather distant. 



There is a row of rudimentary polyps, 17 in one specimen and but 4 

 in another. The spaces between the lateral calyces, mai'gin to margin , 

 are about 5 mm. 



Zooids: The ventral zooids are in two regular rows, one on each 

 side of the dorsal surface, very regularly spaced. Opposite each of 

 the calyces these rows become double. Sometimes there are one or 

 two on the outer side of the base of each calyx, and there are often 

 one or two opposite the inner margin. The zooids are conical or 

 dome-shaped, with distinct apertures. They bear small needle- 

 shaped spicules in their walls. 



The rachis ends distally in a blunt, rounded point projecting 3.5 

 mm. above the last calyx. 



The spicules have already been described. The bar-shaped forms 

 in the polyps are sometimes almost fiddle-shaped. 



Color: Rather dull grayish-brown throughout. 

 48702°— Proc.N.M.vol.43— 12 i 



