64 BULLETIN 77, UlSriTED STATES NATIOISTAL MUSEUM. 



the zocEcia after the stolonal portion has been left behind, and the 

 marked difference between the stolon and the zooecium proper. In 

 C. delicatula the angle of divergence is so small (15°), and the increase 

 in the zooecial diameter so gradual that it is difficult to discriminate 

 between the stolon and the zooecium proper. C. harheri, however, 

 with equally slender and long stolons, has an angle of 30°, which is 

 sufficient to cause the zooecium to stand out prominently. Compari- 

 sons of equally magnified views of this and related species indicate 

 the unusually large size of the zooecium m C. larberi, although its 

 stolon has practically the same dimensions as the more delicate forms. 

 The dimensions of the species are as follows: An average zooecium, 

 including the stolon, is 1 mm. long and 0.23 mm. wide at its greatest 

 diameter. The angle of divergence, as noted before, is 30°. 



Occurrence. — Common in the Middle Ordovician (Ottosee) shales 

 in east Tennessee and southwest Virginia. Specimens indistinguish- 

 able from the types occur in the Lyckholm limestone (Fl), incrust- 

 ing Halysites, at Hohenholm, island of Dago, Baltic Sea. 



Holotype.—C&t. No. 57105, U.S.N.M.; Paratype, Cat. No. 57106, 

 U.S.N.M. 



One specimen from the Lyckholm limestone, island of Dago, is in 

 the collections of the British Museum. 



CORYNOTRYPA INFLATA (Hall). 



Text fig. 10. 



Alecto inflata Hall, Nat. Hist. New York, Pal., vol. 1, 1847, p. 77, pi. 26, figs. 7a, h. 



Eippothoa inflata Nicholson, Pal. Ohio, vol. 2, 1875, p. 268, pi. 25, figs. 1-16. 



Stomatopora inflata Vine, Quart. Journ. Geol. Soc. London, vol. 37, 1881, p. 615. — 

 Ulrich, Journ. Cincinnati Soc. Nat. Hist., vol. 12, 1890, p. 176, fig. 3c; Geol. 

 and Nat. Hist. Surv. Minnesota, Final Rep., vol. 3, pt. 1, 1893, p. 117, pi. 1, 

 figs. 13-21; Zittel's Textbook of Paleontology (Eng. ed.), 1900, p. 261, fig. 

 412B.— Simpson, Fourteentli Ann. Rep. State Geologist New York for the 

 year 1894, 1897, p. 597, figs. 202-204.— Ruedemann, Bull. New York State 

 Mus., No. 49, 1901 [1902], p. 12, pi. 1, figs. 2, 3.— Cumings, Thirty-second 

 Ann. Rep. Dep. Geol. Nat. Res. Indiana, 1907, p. 886, pi. 32, figs. 1, la. 



Corynotrypa inflata Basslek, Proc. U. S. Nat. Mus., vol. 39, 1911, p. 515, text figs. 

 12, 13, 14. 



A single specimen from the Wesenberg limestone has characters 

 so typical of this abundant American form that I have no hesitancy 

 in identifying it as above. The essential characters of Corynotrypa 

 injiata are as follows: 



Zoarium adnate, usually upon ramose or solid bryozoans or bra- 

 chiopods; zooecia typically short, pyriform, with the stolon but 

 slightly developed; eight or nine zooecia in 5 mm.; angle of diver- 

 gence averaging 40°. Exclusive of the stolon, a single zooecium is 

 0.4 mm. long and 0.26 mm. wide. The aperture has a distinct peri- 



