118 PEOCEEDINGS OF THE NATIONAL MUSEUM vol.72 



Genus MUCRONELLA Hincks, 1880 



MUCRONELLA EGYPTIACA Waters, 1909 



Plate 17, Figures 1-5 



1909. Smittia egyptiaca Waters, Bryozoa from the Red Sea, Linnean 

 Societj^'s Journal, Zoology, vol. 31, p. 157, pi. 15, fig. 6, 9. 



-,, ^ * ^ J)^a = 0.10-0.12 mm. 



Measurements. — Aperturei, „,„ 



^ lZa = 0.12 mm. 



ry . |i2 = 0.40-0.60 mm. 

 Zooeciai, „ .^ 



U2: = 0.40 mm. 



Affinities. — The colonies encrust probably small ramified algae ^ 



they have the aspect of small, hollow bifurcated tubes of 5 mm. 



diameter. Because of this particular form the zooecia have variable 



micrometric measurements; our photographs represent the most 



regular cells. 



The lyrule is broad and little salient ; the small cardelles are almost 



on the transverse median axis of the aperture. The mucro is little 



salijent. The small oral avicularium is very inconstant. 



We have seen no essential differences from Water's species. If the 



cells appear more regular, the same colony bears others absolutely 



analogous to those illustrated by this author. In their ensemble, the 



micrometric measurements are identical. Our specimens were living 



and ovicelied. 



Occurrence.—AThatross Station D. 2389, Gulf of Mexico; 29° 28^ 



00'' N.; 87° 56' 00" W.; 27 fms.; gray sand, broken 



shells. 



Red Sea; Khor Dongola; Engineer Island; Has el 



Millau, Sinai Coast (Waters) . 



Plesiotypes.— Cat. No. 7561, U.S.N.M. 



Genus PALMICELLAEIA Alder, 1864 



PALMICELLARIA AVICULIFERA, new species 



Plate 17, Figures 14-16; text Figure 22 c, d 



Description. — The zoarium encrusts grains of hard clay. The zooe- 

 cia are distinct, separated by a deep furrow, large, cyUndrical; the 

 frontal is smooth, very convex, surrounded by very small scattered 

 areolar pores. The aperture is semielliptical and transverse, with a 

 slightly concave proximal border; it is placed at the bottom of a deep 

 peristomie; the peristome is thick, very salient; it bears a very sali- 

 ent round avicularium, without pivot, and four or five other smaller 

 avicularia irregularly placed. The ovicell is large, globular, some- 

 what transverse, opening widely in the peristomie above the 

 operculum. 



