1910.] NATURAL SCIENCES OF PHILADELPHIA. 497 



attached to Bryozoans. The Bermuda specimens are of larger size, 

 agreeing well with Treadwell's description, with the exception of the 

 form of the abdominal seta?. The long acicular ones described by him 

 occur only on the caudal region; those of the characteristic Hydroidcs 

 form with striated, flaring, conspicuously serrate ends are present on 

 the other abdominal segments. The characteristic basket-like oper- 

 culum readily distinguishes the species, in some instances two fully 

 developed ones occur. It is formed of two chitinous light yellow cups, 

 fitted one above the other, on a long, slender, rather stiff peduncle. 

 The lower is edged with 25 or 30 deep points and the upper has nine 

 strongly curved fang-like spines with three conspicuous outer processes 

 (two pointed lateral and one blunt, more or less elongated, median) 

 situated at the point of greatest curvature; a little above the middle; 

 at the inner base of each fang is a short, erect, blunt process or spinule; 

 in every instance these fangs have their points in contact forming a 

 very pretty basket -like end to the operculum. There is great varia- 

 bility in the size of the blunt median process, which is sometimes low 

 and broadly rounded and sometimes much elongated and truncated. 



The animals are long (50 mm.) slender rounded, the branchiae about 

 4 mm. The collar setse, characteristic of the group, are horn-colored 

 with stout shaft or manubrium with two, sometimes three, conspicuous 

 tooth-like spines at the base of long tapered ends ; other thoracic 

 setae long and narrow regularly tapered. Uncini much striated with 

 a few (7) strongly curved pointed teeth in profile but showing irregular 

 series when the rather broad exposed surface is in view. Abdominal 

 setse with flaring striated coarsely serrate ends; hair-like along caudal 

 region. 



Eupomatus elegantulus sp. nov. 



The species is readily identified by its large operculum (2^ mm. in 

 diameter). The lower cup edged with 30 or 40 deep narrow points, 

 the upper with 13 very long, very slender, tapered, regularly curved, 

 spreading, simple spines without outer, lateral, or inner spinelets 

 except a long slender much curved spinule at the inner base of each, 

 their points in contact forming a basket-like center. Entire length 

 of body about 20 mm. Branchial lobes simple, short, the branchiae 

 in a semicircle (16 or 18 on each). Thoracic membrane badly mutilated 

 but showing a well-developed collar and free lateral and posterior 

 border. Seven (7) fascicles of setae and six (6) tori in oblique series 

 on thorax. The collar setae with two (2) conspicuous spines at base 

 of moderately long tapered end ; other setae long, very slender with 

 capillary tips. Uncini triangular in outline, the base protruding 



