748 



BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



The tubules are more interstitial than adventitious, for they do not perforate 

 the ovicell. 



Occurrence. Lowest Eocene (Bryozoan bed at base of the Aquia formation) : 

 Upper Marlboro, Maryland (rare). 



Geological distribution. Cretaceous (Vincentown) : Vincentown, New Jersey. 



Plesiotypes.CsA. No. 65457, U.S.N.M. 



B 



FIG. 242. Genus Crisulipora Robertson, 1910. 



A-C. Crisulipora occidentals Robertson, 1930. A. Zoarium, natural size. B. An ooecial in- 

 ternode, X 20, showing its origin in two zooecia in wbose walls the first Glutinous joint (j) oc- 

 curs, and the mode of formation of three branches; also, the ooecium (oc) distinguished by its 

 coarsely punctate wall, with the tubular aperture (oest. t.) and circular oeciopore. The tubes 

 at the distal extremity of the internode, the proximal portions of which only are shown, give 

 rise to another internode. C. A portion of the lower part of a colony showing a rootlet (r) which 

 grows long, penetrating masses of other material ; another which is shorter and possesses a hook 

 (li) or process which has laid hold of a grain of sand or a pebble; and a stolonlike process (sto) 

 which grows horizontally sending up zooecia at intervals which produced new branches. From 

 the first zooecium (zoe) there arise two tubes one of which gives rise to a double joint (dj.) 

 giving off branches at an angle to each other and hence in different directions. (A-C, after Rob- 

 ertson, 1910.) 



