596 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxiv. 



This was the handsomest alcyonarian that the writer has ever seen 

 as it came up in the trawl. Nothing could be more graceful than the 

 arrangement and attitude of the slender, symmetrical branches. 



The species differs from Iridogorgia pourtalesii in having more 

 closely approximated branches, shape, and spiculation of polyps, as 

 well as in size. 



Colonies branched ; twigs borne on only one side of branches ; cor- 

 tex and pol}^) walls thick ; tentacles capable of retraction within the 

 body cavity. 



Genus PLEUROGORGIA Versluys. 



Colony palmate; branchlets in a straight row on one side of 

 branch, and all in the same plane; polyps arranged in a thickly set 

 row on one side of branchlets. 



PLEUROGORGIA MILITARIS, new species. 



Plate XLVI, flg. S; plate LI, fig. 2. 



Colonj^ incomplete, consisting of a straight smooth stem about 112 

 mm. long, giving off unilateral branches which are 8 mm. apart and 

 all in the same plane. The branches are very slightly curved, but not 

 bent or geniculate; their surface is smooth, and on their upper sides 

 are borne the equidistant jiolyps which are about T mm. apart. On 

 another specimen of the same species the stem bears a row of similarly 

 spaced polyps opj^osite the branches, each being about one-third the 

 length of an internode below the branch origin on the opjDOsite side. 



The polyps are rather slender, cylindrical, 3 mm. high to base of 

 tentacles, the broadest part being beneath the tentacle bases. They 

 stand erect, nearly at right angles to the branch, but are sometimes 

 inclined toward the distal end. The tentacles are long, nonretractile, 

 with conspicuous fringes. 



Spicules long, needle-shaped, forming eight very conspicuous lon- 

 gitudinal bands in polyp walls, ending in acute j^oints at tentacle 

 bases. Tentacle spicules few or entirely wanting. The cortex ap- 

 pears smooth, but contains a very thin layer of scale-like spicules 

 with jagged ends, longitudinally disposed. 



Color of stem, dark brown with slight iridescence; branches and 

 polyps lighter brown. 



Ttjpe.—Q.2ii.^o. 25334, U.S.N.M., Albatross Station 4093, northeast 

 approach to channel between Maui and Molokai, 1171 fathoms. 



This Avas one of the deepest successful hauls made during the cruise. 



The name militaris Avas suggested by the stiff regularity of the 

 attitude of the polyps. 



