238 BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



Genotype. Hoplocheilina spectabilis Canu, 1911. 

 Range. Cenomanian-Maestrichtian. 

 The species of this genus are : 



Hoplocheilina (Eschara) osculifera Eeuss, 1877. Cenomanian, Germany. 

 Hoplocheilina (Eschara'] ichnoidea Hagenow. 1851. Muestrichtian. Belgium. 

 Hoplocheilina (Reptescharellina) prolifera Gabb and Horn, 1862, Danian of 

 New Jersey. 



Hoplocheilina (LepmH.a) russetti Pergens, 1893. Maestrichtian, Belgium. 

 Hoplocheiliiui up, ctnli'ilis Canu, 1911, Rocanean, Argentina. 



Subfamily LUNULARIIDAE Levinsen, 1909. 



The zoarium is a Lunulites that is, a conical, cupuliform disk. Vibracula are 

 present. The opesiular indentations are very inconstant. 



The only known genus is Lumdaria, the structure of which is described below 

 as a result of our own studies. 



Genus LUNULARIA Busk, 1884. 



1SS4. Litnularia BUSK, Report on Polyzoa collected by Challenger, Cheilostouiata, vol. 10, 

 pt. 30, p. 208. 



The zoarium has the Lunulites form. The avicularia are symmetrical. Ex- 

 teriorly and interiorly the zooecia are arranged in radial rows. The cryptocyst is 

 more or less developed. Both radicular and hydrostatic zooecia are present. The 

 ovicell is endozooecial. 



Genotype. Lunulites capitlus Busk, 1884. 



Range. Cenomanian Recent. 



Historical. Lunulites Lamarck 1812 is not a definite generic type, but is 

 merely a zoarial form adopted for certain reasons. This style of growth obtains 

 in many genera of cheilostomatous bryozoa, as Otionella and Trochopora in the 

 Anasca McAacostega; Lunnlaria and Selcnaria in the Anasca Coilostega and 

 Stichopora, Fedora, and Bipora in the Ascophora. 



All of the fossils hitherto grouped under the general name of Lunulites must 

 now be classified according to their affinities. In 1900. Canu made the first and 

 timid attempt. In 1912, Waters brought forth anatomical proof, which will be 

 cited when the occasion demands. 



Structure of the Lunulites. The hydrostatic zoarial system of the Lunulites 

 bryozoa is very complicated and we are still ignorant of many of the details. The 

 larva ordinarily attaches itself firmly on a grain of sand. The ancestrula which is 

 derived from it immediately gives rise to some closed hydrostatic zooecia which 

 by their lightness permit the zoarium to commence its growth by ascending away 

 from the sand dangerous to its development. (Aborted zooecia of D'Orbigny.) 

 When in the vicinity of algae, the zoarium remains fixed under their fronds. 

 When they do not offer sufficient shelter, the closed zooecia transform themselves 

 into perforated, calcified zooecia which are radicular; the radicles then attach the 

 zoarium to shells, stones, or small algae. The zoarium continues to develop in 



