520 





PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 39. 



average length of stolon, 0.17 mm.; four to four and one-half zooecia 

 in 3 mm.; angle of divergence about 50°. 



Occurrence. — Apparently rare in the Richmond group, 3 miles 

 north of Spring. Valley, Minnesota. 



Holotype.— Cat. no. 57110, U.S.N.M. 



CORYNOTRYPA TURGIDA (Ulrich). 



Stomatopora turgida Ulrich, Journ. Cincinnati Soc. Nat. Hist., vol. 12, 1890, 

 p. 176, fig. 3; Geol. and Nat. Hist. Surv. Minnesota, Final Rep., vol. 3, pt. 1, 

 1893, p. 118, pi. 1, figs. 22, 23. 



Original descrij^tion. — "Zoarium adnate, consisting of a single 

 branching series of zooecia. Zooecia comparatively very large, the 



I 



Fig. 20.— Corynotrypa turgida. a and 6, the type-specimen, natural size and X9. Richmond 

 GROUP (Fernvale formation), Wilmington, Illinois. (After Ulrich.) c, a specimen, X9, 

 FROM THE Richmond group, 3 miles north of Spring Valley, Minnesota. 



anterior half much swollen, rapidly tapering posteriorly, with the 

 slender, tubular proximal end inserted beneath the turgid anterior 

 end of the preceding zooecium. Five zooecia in 5 mm.; length of 

 each zooecium varying from 0.85 to 1.30 mm.; the greatest diameter 

 of the anterior half from 0.4 to 0.6 mm. The longest cells are the 

 least turgid, while the shortest are the most. • Apertures round, 

 bordered by an elevated margin, small, 0.1 mm. in diameter, and 

 situated about one-fourth of the length of the zooecium from its 

 anterior end." 



