XORTH AMERICAN EARLY TERTIARY ERYOZOA. 



257 



considered. We luive studied i\ number of species with a faceted cryptocyst, notably 

 Membranipondra spissimuralis. It is not certain that the Cretaceous species are 

 provided with onychocellaria. for these structures are perhaps interzooecial avi- 

 cularia, of a special type now extinct. In the interior the polypidian tube is 

 analogous to that in .\f!i>idoxtoma Ilincks, 1881; it is a thick- 

 ening of the proximal border of the aperture. 



The species of the genus are : 



Euritina (Eschara) eurifa D'Orbigny. 1.8r>i_'. 



Euritina wclxehi Canu, 1900. 



Euritina lata Canu, 1911. 



Euritina elongata Canu, 1911. 



EuritiiKt inti'i-incd/n Canu, 1911. 



Euritina (Biflustra) tort a Gabb and Horn, 1862. 



Euritina (Vincitlaria) rmtcHis D'Orbigny, 1852. 



EURITINA TORTA Gabb and Horn, 1862. 



Plate 1. fig. 16. 



1862. Bifluntt-ii torta GABR and HORN, Monograph of the Fossil 

 Polyzoa of the Secondary nnd Tertiary formations of 

 North America, Journal Academy of Natural Sciences, 

 Philadelphia, ser. 2, p. 152. pi. 20, fig. 36. 



1901. Biflustra turta ULBICH, Maryland Geological Survey, Eocene, p 

 1909. Biflustra torta WELLES, Cretaceous Faunas, Geological Survey 

 p. 332. 



. rA0=0.25mm. . \Lz- 



Aleasurements. Opesia { , Zooccia{ 7 



7o=0.12-0.15 mm. lfe= 



FIG. 68. Genus Euri- 

 tina Canu, 1900. 



Euritina (Eschara) eu- 

 rita D'Orbigny, 1852. 

 Zooecia with ovicells, 

 X 20. 



214, pi. 60, fig. 7. 



of New Jersey, vol. 4, 



=0.40-0.45 mm. 

 0.25-0.30 mm. 



The zoarium is bilamellar; the two lamellae are back to back and may be 

 separated. The cryptoeyst is deep and the two grooves which separate it from the 

 mural rim are quite visible. 



The onychocellarium is straight, symmetrical, oval; the beak is salient in front 

 of the zooecial plane; there is no pivot. 



At the base of our figure there is a regenerated zooecium. 



"Although rather variable this is still to be counted as an easily recognized 

 species. Ovicells occur but rarely, only four or five specimens out of fifty or more 

 in my collection having any at all. They are cucullate often with a delicate longi- 

 tudinal ridge across them and uniformly convex." (Ulrich 1901.) 



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

 Marlboro, Maryland (rare). 



Geological distribution. Upper Cretaceous (Vincentown limesand) : Mullica 

 Hill. Timber Creek, and Vincentown, New Jersey. 



PlesiotypeCat. No. 63778, U.S.N.M. 

 55899 19 Bull. 106 - IT 



