66 PROCEEDINGS OF THE NATIONAL MUSEUM vol.67 



cent, arranged in transverse rows (fig. 2) and more rarely in 

 quincunx (fig. 6) . Opercula are frequent (fig. 2) . 



The eleocellaria are ordinary zooecia in which the aperture is 

 elongated and presents two lateral denticles (fig. 4) . 



The chief characteristic of this species is the frequent presence of 

 a tranverse fossette placed below the aperture (fig. 5). The fusion 

 of this fossette with the aperture engenders the eleocellarium 

 (fig. 4) . The longitudinal section of this species has been figured by 

 Gregory. 1899. The ovicell is unknown. Figure 7 represents 

 an arrest of development, resulting in a false base. 



Measu remen ts. — 



* . {ha = 0.16-0.18 mm.l ^ .. [hf = 0.44 mm. 

 Aperture ii ^ on ) J^acettes {it ^aa 



^ [la==0.20mm. J [11 = 0.44 mm. 



Diameter of the branches, 3 mm. 



Affinities. — This species is very well characterized by the nature 

 of its eleocellaria and by the transverse fossettes which adorn a cer- 

 tain number of zooecia. 



Occurrence. — Lower Cretaceous (Aptian) : Faringdon, England 

 (common) . 



Plesiotype.—C&t. No. 69917, U.S.N.M. 



MELICERITITES SEMICLAUSA Gregory, 1899 



Plate 11, figs. 12, 13 



1872. Meliceritites gracilis Reuss, Die Bryozoen und Foraminiferen des unteren 

 Planers, Paleontographica, vol. 20, pt. 1, p. 120, pi. 29, figs. 12-16 (not 

 synonymy). 



1899. Meliceritites semiclausa (part) Gregory, Catalogue of the Cretaceous 

 Bryozoa in the British Museum, vol. 1, p. 328, pi. 14, fig. 2 (not figs. 1, 3) . 



Affinities. — Our examples correspond almost exactly in aspect and 

 measurements with the specimen figured by Gregory (pi. 14, fig. 2), 

 the single slight difference being in the more elongate form of the 

 eleocellarium. 



The ovicell belongs to the group of Meliceritites transversa in its 

 great width. Unfortunately, the ovicell of our figured specimen was 

 broken. 



The species differs from Lohosoecia semiclausa Michelin, 1845, in 

 its much larger micrometric measurements, in the presence of an 

 eleocellarium, and in its semicircular aperture. 



Measurements. — 



» , fha=? ] T? ^.^.^ |hf = 0.40-0.48 mm. 



Aperture |j^ ^o.l2-0.16 mm.} Facettes |j^ ^o.27-0.30 mm. 



Diameter of large branches, 2 mm. 

 Occurrence. — Lower Cretaceous (Aptian): Faringdon, England 

 (rare) . 



