2 i 2 REPORT OF NATIONAL MUSEUM, lb!J7. 



sometimes mixed with spouge spicules, firmly united by a brown cement 

 substance; arms tubular, termiuatinj^- in simple rounded apertures. 

 Localities. — •North Atlantic, and the Caribbean !Sea (stations 2115, 

 2150, 2234, 2571), 380 to 1,350 fathoms. 



Genus RHIZAMMIN A. 



Unattached masses of line, flexible, simple or branching* chitino- 

 arenaceous tubes. 



RHIZAMMINA INDIVISA Brady. 

 (Plate IT), li..-. 2.) 



Slender, flexible, simple, chitinous tubes of a brownish color, thickly 

 incrusted \vith small foraminifera (mostly Globigeriua) and very fine 

 sand. Test more or less contorted in drying; generally tapering toward 

 the extremities; apertures terminal, simple. Length, 3 to (! mm. (i to 5 

 inch). 



Localities. — Southward of Long Island, the Straits of Yucatan, the 

 Gulf of Mexico, and the coast of Brazil (stations 2234, 2355,2380,2760), 

 400 to 1,400 lathoms. 



RHIZAMMINA ALG^FORMIS Brady. 



(Plate 15, ti.i;-. 1.) 



Slender, chitinous tubes, incrusted with fine sand or small forami- 

 nifera; dichotomously branched; quite flexible while wet, very brittle 

 when dry; found in tangled masses, from which it is extremely difficult 

 to separate an unbroken specimen. Lengtb, indefinite; may be an inch 

 or more; diameter of tube, 0.12 to 0.3 mm. (v^o to -^\- inch). 



Locality. ff the west coast of Mexico (station 3415), 1879 fathoms. 



Family III. LITUOLID.E. 



Test arenaceous, usually regular in contour and more or less definitely 

 segmented; chambers frequently labyrinthic. 



BulDfkiriily LI'i''XJOI.IlsrJS:. 



Test composed of coarse sand grains, rough externally; often laby- 

 rinthic. 



Genus REOPHAX. 



Test free; composed ol" a single flask-shajied chamber, or of several 

 united in a straight, curved, or irregular line; never spiral. 



REOPHAX DIFFLUGIFORMIS Brady. 



(Plate 16, lig. 2.) 



Test free, small, oval, pja'iform, or flask-shaped; walls thin, inclosing 

 a single undivided chamber, and comi)osed of rather coarse mvA firmliy 



