26 BULLETIN 96, UNITED STATES NATIONAL MUSEUM. 



onychocellaria are straight, and their opesium presents a posterior 

 part, narrow and denticulated; the mandil)]e is composed of two 

 membranes. The zooecium is closed by an opercular valve. The 

 mural rim is not separated from the cryptocyst. 



Genotype. — Onychocella solida Nordgaard, 1907. 



Range. — Jacksonian-Eecent. 



VELUMELLA, new genus. 



{Velum., sail, in allusion to the membranes of the mandibles.) 



The retractor muscles of the polypide are attached in the median 

 axis of the zooecium; the opesiular indentations are S3^mmetrical. 

 The onychocellaria are straight, without distal canal; the rachis of 

 the mandible bears two broad membranes; the opesium of the ony- 

 chocellarium is elliptical and entirely denticulated. The operculum 

 is a wholly chitinized simple one, not separable from the ectocyst. 

 Multiporous septulae. The mural rim is distinct from the cryptocyst. 



Genotype. — Velumella {Onychocella) levinseni, new name.^ 



DIPLOPHOLEOS, new genus. 

 {Diploos, double; pholeos, den of an animal.) 



The retractor muscles of the poh'pide are attached in the median 

 axis of the zooecium. The lateral indentations are symmetrical and 

 almost transformed into true opesiules. The onychocellaria are 

 straight, their opesium is oval, with a denticulated poster ; the mandi- 

 ble (onychocellium) is bimembranous. The mural rim is not sepa- 

 rated from the cryptocyst. The zooecium is closed by an operculum 

 attached to the ectocyst. The axis of rotation of the operculum is in- 

 dicated by two opesial denticles. The zooecial opesia are dimorphous ; 

 one kind is elongated and the other transverse. 



Genotype. — Dipdoplioleos fusiforme., new species. 



Range. — Jacksonian, Vicksburgian. 



DIPLOPHOLEOS FUSIFORME, new speciea. 



Plate 3, fig. 2. 

 Description. — The zoarium incrusts shells and pebbles. The zooecia 

 are hexagonal, a little elongated, separated by a narrow furrow or 

 united among themselves by their mural rims; the cryptocyst is 

 deep, concave, shorter than the opesium, finely granular; the po- 

 lypi dian convexity is protruding, wrinkled or granulated, denticu- 

 lated on its opesial border; the lateral openings are deep, round, 

 almost becoming true opesiules ; the opesium is elongate, semilunate, 

 finely crenulated. The ovicell is an inconspicuous distal convexity, 

 sometimes limited by two lines of lateral suture. The onychocel- 



1 This new name is proposed for the recent species figured as Onychocella species by 

 Levinsen in his Morphological and Systematic Studies on the Cheilostomatous Bryozoa, 

 1909, pi. 22, figs. 3a-d. 



