150 BULLETIN 125, UNITED STATES NATIONAL MUSEUM. 



PALMICELLARU COSTULATA. new species. 

 Plate 45, figs. 12, 13. 

 Description. — The zoarium incrusts corals. The zooecia are distinct, separated 

 by a broad furrow, little elongated; the frontal is very convex, thick, covered by a 

 tremocyst with large pores, garnished with broad radiating costules, and ending in a 

 very salient avicularium. The apertui'a is semielliptical, transverse, deeply bmied, 

 partially hidden by the avicularian mucro. The ovicell is deeply embedded in the 

 distal zooecium; it is large, little salient, similarly covered with large radiating 

 costules. 



,, . * . fAa = 0. 09 mm. „ . fiz = 0. 45-0. 50 mm. 



Measurements. — Apertura , _ , „ Ziooecia , „ ^ ^ 



^ lZa = 0. 13 mm. l(z = 0. 40 mm. 



Affinities. — In the vicinity of the ancestrula the avicularian mucro is not con- 

 stant; it is often replaced by small salient orbicular avicularia irregularly arranged 

 around the apertura. 



This beautiful species on account of its frontal irregularities is very difficult to 

 photograph. Better preserved specimens, moreover, will probably show new char- 

 acters necessitating its classification in another genus. The species is certainly 

 shorter than Lepralia corrugata MacGillivray, 1895, which has some resemblance. 



Occurrence. — Pleistocene: Mount Hope, Panama Canal Zone (rare). 



Coty pes. —Cat. No. 68654, U.S.N.M. 



PALMICELLARIA CONVOLUTA Ulrich and Bassler, 1904. 



Plate 23, figs. 1-3. 



1904. Palmicellaria convoluta Ulrich and B.\ssler. Maryland Geological Survey, Miocene, p. 427, 

 pi, 16, figs, 2-4, 



The original description of this species is as follows: 



Zoarium erect, forming loose masses 3 cm, or more in diameter, consisting of broad, bifoliate, con- 

 voluted, anastomosing loaves, 1,0 mm. or more in thickness. Zooecia prominent, distinct, oval, rhom- 

 boidal or hexagonal, arranged in irregular quincunx, averaging between 0.9 mm, and 1.0 mm. in length 

 and about 0.45 mm. in width: surface rather coarsely punctured; orifice terminal, the proximal edge over- 

 hung by a prominent mucro containing an a^-icularium the sagittate opening of which is divided into 

 two unequal parts by a septum and lies on the abrupt distal slope of the mucro so as to be nearly or en- 

 tirely concealed in a front view. When the apex of the mucro is worn or broken away the cavity of the 

 avicularium is exposed to view as a cell immediately behind the orifice and almost equaling it in size. 

 0\'icells small, transverse. Inilbous, closely united to the cell next above. 



itf 4 \ i (Aa=0. 15 mm. „ . fL2=0. 85-1. GO mm. 



Measurements. — Apertvu-a , - __ Zooecia , „ . ^ „ ,.^ 



^ I to = 0. 20 mm. I Z2 = 0. 45-0. 50 mm. 



The essential features of this species are noted in the original description. 



Occurrence. — Miocene (Calvert formation) : Reeds, Maryland (rare) . 



Cotypes.— Cut. No. 68655, U.S.N.M. 



PALMICELLARIA PUNCTATA Ulrich and Bassler. 1904. 



Plate 23, fig. 4. 



1904. Palmicellaria punctata Ulrich and Bassler, Marvland Geological Survey, Miocene, p. 428, 

 pi. 116, fig. 1. 



Only the type specimen of this species, a fragment of bifoliate zoarium, is 

 known, and our studies upon it must remain incomplete. This specimen shows 



