No. 1797. 



NEW TUBULTPOROTD BRY0Z0A—BAS8LER. 



513 



CORYNOTRYPA TENUICHORDA (Ulrlch and Bassler). 



Stomatopora tenuichorda (temnichorda in error) Ulrich and Bassler, Geol. Surv. 

 New Jersey, Paleontology, vol. 4, 1907, p. 314, pi. 20, figs. 5, 6. 



Original description. — ''Zoarium adnate, frequently brandling, con- 

 sisting of uniserially arranged zocecia. Zooecia elongate-pyriform, or 

 club-shaped, 0.45 mm. to 0.75 mm. in length, about 0.02 mm. in 

 width at the posterior extremity, increasing very gradually in size 

 through about one-half their length, and then somewhat abruptly to 

 about 0.15 mm. at the rounded anterior end. Zooecial aperture 

 nearly terminal, small, circular, with a slightly elevated, rim-Uke 

 border, fi'om 0.035 mm. to 0.05 mm. in diameter." 



Tliis delicate species is represented in the collections of the National 

 Museum by a number of specimens, a portion of the best preserved 

 one of which is shown in figure 1 1 . While the general aspect of the 

 species is precisely the same as in 

 others of the C. delicakila group, 

 a slight constriction in the middle 

 portion of the zooecium proper 

 causes a noticeable swelhng in 

 its proximal portion, giving an 

 appearance somewhat similar to 

 that often seen in certain forms 

 of Ilippothoa. None of the speci- 

 mens shows any other features 

 characteristic of Hipjjothoa, and 

 all agree with Corynotrypa in 

 every respect save the one char- 

 acter mentioned. Until more 

 evidence is at hand, the species 

 may be regarded as a typical Cory- 

 notrypa, differing from the other 

 narrow, elongate species in having a greater angle of divergence (30°), 

 and in the proximal swelling of the zooecia mentioned above. 



Occurrence. — Not uncommon in the Vincentown sand of the Cre- 

 taceous, at Vincentown, New Jersey. 



Holotype.— Cat. no. 52618, U.S.N.M. 



CORYNOTRYPA INFLATA SECTION. 



The angle of divergence obtaining in species assigned to the C. 

 delicatula section is usually so small that the stolon and the expanded 

 part of the zooecium blend together to produce a structure which 

 varies only in length. The variability in this section, therefore, 

 although just as great, is not so conspicuous as in the C. injlata 



Proc.N.M.vol.39— 10 35 



Fig. 11.— Corynotrypa tenuichorda. a, portion 



OF A WELL PRESERVED ZOARIUM, X9, INCRUST- 

 ING THE INTERIOR OF A PELECYPOD ; 6, ZOCECIA 

 OF THE SAME ZOARIUM, X20. CRETACEOUS, VIN- 

 CENTOWN SAND, Vincentown, New Jersey. 



