ai:t.2i CYCLOSTOMATOUS BRYOZOA CANU AND BASSLER 43 



Measurements. — Diameter of orifice, 0.10 mm.; diameter of peri- 

 stome, 0.14 mm.; distance of peristomes, 0.30 mm.; separation of 

 peristomes, 0.40 mm. 



Variations. — The tubes with prominent threads are visible only 

 on the specimens with worn and little salient peristomes. The sepa- 

 ration of the peristomes can be measured only on specimens where 

 they are arranged in quinqunx. 



The ovicell is somewhat different from that in other species and 

 resembles Trigonoecia. It differs, nevertheless, in the absence of 

 transverse wrinkles. Moreover, we know that the typical expanded 

 form visible on the lamellar zoarium disappears easily on these cylin- 

 drical specimens. 



Structvre. — The sections are, indeed, those of the genus Cardioecia. 

 In longitudinal section the tubes are club-shaped, with moniliform 

 walls, })ut very thick and strongly calcified; the gemmation is tri- 

 parietal on the median lamella. 



In transverse section the tubes are orbicular or elliptical, with 

 diameter increasing toward the periphery. The walls here are very 

 thick. 



Occurrence. — Lower Cretaceous (Valangian) : Sainte-Croix (Vaud), 

 Switzerland. 



Cotypes.—C&t. No. 69891, U.S.N.M. 



CARDIOECIA HYSELYI De Loriol, 1869 



Plate 3, figs. 5-8 



1869. Mesenteripora hyselyi De Loriol and Gillieron, Monographie paleon- 

 tologiqiie de rUrgonian de Landeron, Memoires Soci6t6 helvetique des 

 Sciences naturelles, vol. 23, p. 40, pi. 3, fig. 1. 



Measurements. — Diameter of aperture, 0.12 mm.; diameter of peri- 

 stome, 0.26 mm.; diameter of tubes, 0.24 mm.; distance of peri- 

 stomes, 0.40-0.70 mm.; separation of peristomes, 0.52-0. GO mm. 



Affinities. — We have not examined De Loriol's figured type and 

 we are not very certain of our determination. De Loriol's tlescrip- 

 tions and figures were always incomplete and inexact. 



The tubes arc visible or invisible; the peristomes are little or very 

 salient, sometimes arranged in verticells. The ovicell is cordiform, 

 rather regular, little convex. The zone of growth is thick. 



The sections are identical with those of Cardioecia neocomiensis 

 D'Orbigny, 1853, but the present species, which has a similar exte- 

 rior aspect, differs in its larger peristomes and in its foliated and 

 much broader fronds. 



Occurrence. — Lower Cretaceous: Sainte-Croix (Vaud), Switzer- 

 land; (Valangian), Landeron (Neuchatel), Switzerland (Urgonian). 



Plesioty pes. —Cat. No. 69892, U.S.N.M. 



