68 THE DEVONIAN OF MISSOURI. 



branches at about the third division, whereas here they are well differentiated to at 

 least the sixth." 



Occurrence — Springer figures 3 specimens. Probably all are from the Snyder 

 Creek shale type locality on Craghead Creek. The figures on plate seven are all from 

 Mr. Rowley's original type, from the same locality. 



MOLLUSCOIDEA 



Class BRYOZOA 



Order Cyclostomata 



Family Fistuliporidae 



Genus Cyclotrypa Ulrich 



Cyclotrypa communis Ulrich 



Plate 9, figures 7-9. 



1890. Fistulipora communis Ulrich, Geol. Surv. Illinois, VIII, p. 476, pi. 47, figs 1 



and la; pi. 48, figs. 1 and la. 

 1896. Cyclotrypa communis Ulrich, Zittel's Textbooks of Paleontology (Engl, ed.), 



vol. I, p. 269, fig. 443. 

 1913. Cyclotrypa communis Bassler, Zittel's Textbook of Paleontology (Engl, ed.), 

 vol. I, 2nd ed., p. 329, fig. 470. 

 Ulrich 's description — "Zoarium explanate, commonly attached to foreign bodies, 

 at other times free and provided with an epitheca, often composed of layers, each a 

 mm. or two in thickness. The surface is raised into low, broad, rounded monticules 

 two or three mm. wide, and their summits three or four mm. apart. Apertures circular 

 with a very thin but distinctly elevated peristome, generally about 0.16 mm. in dia- 

 meter, but attaining a diameter of 0.25 mm. near the summits of the monticules; dis- 

 tances apart rather variable, those in the monticules more separated than the other. 

 In the intermediate spaces five or six occur in two mm. When the surface is worn the 

 apertures appear quite small and the interspaces very wide. Zooecia thin walled, circu- 

 lar or oval, provided with two or three distant diaphragms. Lunarium obsolete. Vesicles 

 thin-walled, generally wide and shallow, about two-thirds as wide as the zooecia, sur- 

 rounding them in two or more series and forming large clusters under the monticules. 

 In good tangential sections the vesicle spaces exhibit one or more subcentral minute 

 spots, which probably represent perforations in their covers." 



Remarks — This is a common form in the Mineola. It is often attached to foreign 

 bodies, the coral Ceratopora grabaui Branson being one of its favorites. The speci- 

 mens show very few zooecial openings at the top of the monticules, and no subcentral 

 spots have been observed in the vesicle spaces. 



Occurrence — Mineola of Montgomery and Warren Counties. 



Cyclotrypa magna-monticulata n. sp. 

 Plate 9, figures 4, 5, 16; plate 10, figures 1, 3, 6. 



Though several specimens of this species have been collected, the description is 

 based mainly on a well-preserved impression and on part of a well-preserved zoarium. 

 The zoarium impression is nearly semicircular with a radius of about 3 cm. The original 

 was strongly concave, the center being depressed about 2 cm. below the edges. 



The most striking characteristics of the specimen are the large size of the monti- 

 cules and their large distance apart. They range from 1 to 2 millimeters in height, from 



