154 PROCEEDINGS OF THE NATIONAL MUSEUM. voL.xxii. 



PLASMOPORA LAMBII, new species. 



This species begins growth on some small foreign object, aud expands 

 to a diameter exceeding 12 cm. by 7 cm. in height. Beyond the place 

 of attachment the lower surface is irregularly concave and covered by 

 a thin epitheca. The upper surface is in form depressed hemispheric 

 to conical. Corallites from 1 to 1.75 mm. in diameter, commonly about 

 1.25 mm., circular, and separated from one another from 0.5 to 1.25 mm. 

 Septa not prominent, and where the original surface is well preserved 

 not easily distinguishable from the radial striations, or granular sur- 

 face, of the tubular area. Corallites with very closely adjoining tabula3, 

 which are generally decidedly vesicular, but in places they are flat. In 

 longitudinal sections there are from two to five tubules between neigh- 

 boring corallites; the tabulie are convex, generally giving the inter-cor- 

 allite space a decided vesicular structure. 



The general vesicular condition of the tabulae in both the tubules and 

 corallites distinguishes P. lambii. This feature was pointed out by Mr. 

 Lawrence M. Lambe of the Canadian Geological Survey, and the writer 

 takes pleasure in connecting his name with this new species in appre- 

 ciation of his excellent work on the corals of Canada. 



Collectors. — J. N. Carpender, A. H. White, and A. V. Shaw. Cat. 

 No. 28140, U.S.N.M. 



CALAPOECIA CANADENSIS Billings. 



For synonymy see Lambe, Geol. Snrv. Canada, Cent, to Canadian Pal., IV, 1899, 

 p. 43. 



Of this species, there is a small, depressed, hemispheric specimen in 

 which the corallites are in contact, and therefore there is little inter- 

 zooecial vesicular tissue. The hexagonal, nearly uniform corallites are 

 from 3 to 4 mm. in width, and each has from 18 to 20 septa. 



The above identitlcation is confirmed by Mr. Lawrence M. Lambe. 



Collector.— J. N. Carpender. Cat. No. 28142, U.S.N.M. 



Order MADREPORARIA Edwards and Haime 



Suborder TETRACORALLA Haeckel. 



Family STREPTELASMID^ Nicholson. 



STREPTELASMA CORNICULUM Hall. 



Streptelasma corniculmn Hall, Pal. N. Y., 1, 1847, p. 69, pi. xxv, figs, la-le.— WiN- 

 CHELL and ScHUCHERT, Geol. Minn., Ill, Pt. 1, 1893, p. 90, pi. G, figs. 20, 21. 



This characteristic Trenton cup coral is common in the strata of Silli- 

 man's Fossil Mount, and agrees well with specimens from the Galena 

 horizon of Minnesota. 



Collectors. — J. N. Carpender, A. V. Shaw, and A. H. White. Cat. 

 No. 28141, U.S.N.M. The American Museum of Natural History has a 

 number of specimens collected by Mr. R. W. Porter. 



