666 A. JEJ. Yerrill — Turhellaria, Nemertina, and 



nate, so that tlie}^ somewLat resemble narrow feathers, hence the 

 name. Their form is unusual in the genus, but is similar to that of 

 P, denticulatiis St. Joseph. 



Color, in life, bright red. Length, about 35"'™. In dead corals. 



Polycirris luminosus, sp. nov. 



A third species of Polycirrus has long, slender, simple setae on at 

 least 31 anterior segments, accompanied by long rows of minute 

 uncini after the 7th segment. 



The setae are numerous in the 17 anterior fasicles, of two sizes, 

 the larger about ^ as long as the breadth of the body, very slender, 

 not limbate, flexuous, tapering to a long sharp point; the small 

 ones are similar to the larger ones, and about as numerous. On seg- 

 ments 25-31 they are few and small. Uncini begin on the 8th 

 setigerous segment and continue to very near the posterior end, being 

 present on over 40 segments; they form long simple series anteriorly, 

 but back of the 30th segment they are on pinnulae, in smaller rows of 

 10-15, but with very distinct posterior capillary ligaments. The 

 anterior ones are very minute, longer than high, with a shoe-shaped 

 base, a little turned up and subacute anteriorly, and with a promi- 

 nent heel and concave sole ; the upright part is concave above the 

 heel ; the large rostral hook is about half the length of the base, 

 little incurved ; apical denticles 2 or 3, the more distal ones very 

 minute. On the posterior segments the uncini become higher, with a 

 shorter base, and with two minute apical hooks in a side-view. 



Color in life, bright red. It is brilliantly phosphorescent with a 

 bluish light. Bailey Bay, 30-40 feet, among dead corals. 



The descriptions of the two following very interesting species have 

 been prepared by Miss Katharine J. Bush: — 



Sthenelais setosa Bush, sp. nov. 



Although only the anterior portion of an example belonging to 

 the genus Sthenelais was found, it seems so to differ from all the 

 species previously described from the West Indian and southern 

 Atlantic faunoe as to deserve description. 



The 27 segments occupy a length of about 10""™, with a width, 

 including the seta?, of 3™'". 



The cephalic lobe is about twice as broad as long, but little rounded 

 posteriorly and well rounded anteriorly, with a large, trilobed basal 



