274 REPORT OF NATIONAL MUSEUM, 1897. 



REOPHAX DENTALINIFORMIS Brady. 

 (Plate 18, fig. 2.) 



Test cylindrical, tapering, slightly curved, made up of four to six 

 elongate, slightly inflated segments arranged in linear series. Walls 

 composed of rather coarse sand, firmly cemented ; aperture in the pro- 

 longed end of the terminal segment. Length, 1.5 to 3 mm. (^ to £ inch). 



Locality. — Not recorded. 



REOPHAX BACILLARIS Brady. 

 (Plate 18, fig. 3.) 



Long, slender, cylindrical, straight or slightly bent, tapering grad- 

 ually, composed of numerous segments (fifteen to twenty); sutures 

 between the earliest segments indistinguishable, the later segments 

 inflated and the sutures well marked ; aperture simple, in the terminal 

 segment; color, light gray. Length, 1.5 to 3 mm. (-^ to £ inch). 



Localities. — Nantucket Shoals, off Trinidad, south of Cuba, south- 

 east of Marthas Vineyard, off Chesapeake Bay (stations 2041, 2221, 

 2228, 2568, 2723), 1,500 to 1,800 fathoms. 



REOPHAX NODULOSA Brady. 



(Plate 18, fig. 4.) 



A long, cylindrical, tapering, straight or slightly bent test, composed 

 of several (commonly six to ten) oblong or pyriform segments, arranged 

 in linear series, slightly embracing; walls thin, arenaceous, smooth 

 within and without; color, a rich brown; aperture simple, terminal. 

 Section shows the smooth chambers and the thin embracing walls. 



Locality.— Gulf of Mexico (stations 2385,2395), 730 and 347 fathoms. 



REOPHAX ADUNCA Brady. 

 (Plate 18, fig. 5.) 



The distinguishing characteristics of this species are the inflated 

 segments, their nearly equal diameter, and their irregular arrangement 

 in a crooked line of succession. It is of smaller size and coarser 

 structure than the other polythalamous species of Reophax. 



Localities. — Oft' coast of Maryland and in Gulf of Mexico (stations 

 2228, 2338), 1,582 and 189 fathoms. 



REOPHAX CYLINDRICA Brady. 



(Plato 18, fig. 6.) 



Elongate, straight, cylindrical, of nearly even diameter, closed and 

 rounded at the aboral end, constricted at the oral extremity; sutures 

 marking the union of segments almost wholly obscured; aperture 

 simple, central, terminal ; chambers regular in form, separated by thick, 



