84 



BULLETIN 7*7, UNITED STATES NATIONAL MUSEUM. 



CCELOCLEMA CRASSIMURALE, new species. 



Plate 7, fig. 12; text fig. 24. 



This new species is founded upon a single fairly well preserved 

 specimen, 18 mm. long and 5 mm. in diameter. The zooecial layer 

 averages a millimeter in thickness, while the axial tube, now filled 

 with clay, varies from 1 to 1.5 mm. in diameter. The zooecial 

 apertures are rather large, 4 in 2 mm. measuring along their greater 

 length, and are irregularly oval in shape. Maculae are present at 

 regular intervals, and form depressed spaces from which the zocecia 

 radiate somewhat irregularly. Mesopores are numerous, small, and 

 very irregular in shape and position. Both zocecia and mesopores 











I i 



Fig. 24.— Cceloclema crassimubale. a, fragment of a zoarium, natural size, with end view of 



THE SAME SHOWING THE CENTRAL TUBE; 6, TANGENTIAL SECTION, X20, EXHIBITING THE THICKNESS OF 

 WALLS, OBSCURE LUNABIUM, AND SMALL, IRREGULAR MESOPORES; C, VERTICAL SECTION, X20, THROUGH 

 ONE SIDE OF A ZOARIUM. JEWE LIMESTONE (Dl), BARON TOLL'S ESTATE, ESTHONIA. 



have unusually thick walls. The lunarium is inconspicuous both at 

 the surface and in thin sections. 



Although closely related to the typical forms of the genus, O. crassi- 

 murale proves upon comparison to have larger zooecia and thicker 

 walls than any described form. None of the associated bryozoans 

 has a central tube, and this fact alone will aid in its determination. 



Occurrence. — Rare in the Jewe limestone (Dl), Baron Toll's estate. 

 Specimens which are believed to represent the parasitic base of this 

 species have been found in the Jewe limestone associated with the 

 type-specimen, and also in the Wassalem beds (D3), at Uxnorm. At 

 the latter locality no specimens of the erect, hollow stems have been 

 noted. 



Holotype.— Cat. No. 57195, U.S.N.M. 



British Museum's collections, thin section of the type-specimen. 



