12 PALEONTOLOGY OF NEW YORK. 



This species may be distinguished from C. monticulatus by the larger size of 

 tlie cells. 



Formation and locality. Lower Helderberg group, Schoharie, N. Y. 



ClIiETETES MONTICULATUS. 



I'LATK VIII, FIGS. 5-7. 



Ckttteiet mtmticulaiuji. Hall. ThiHy-Beconil Kept. N. Y. Stiite Mus. Nat. Hist, p. 148. 187fl. 

 " " Report of State Geologist for 1882. Expl. jil. 8, &gs. 5-7. 1883. 



CoRALLUM forming spheroidal ma.s.ses. Cell tubes polygonal, generally pentago- 

 nal or hexagonal; diameter from .25 to .85 mm.; walls thin, strongly corru- 

 gated. Septa slightly thinner than the cell walls, occurring at irregular 

 intervals, varying from .33 to 8 mm. or more. On the surface are monticulae, 

 arranged in intersecting rows, the centers of which are distant from each 

 other about 5 mm., with cells of the same size as on other parts of the surfiice. 



This species resembles C. colliculatus, but may be distinguished from that 

 species by its spheroidal I'orm, and its smaller cell tubes. 



Formation and locality. Lower Helderberg group, Schoharie, N. Y. 



NoTK. — Tilt; two jirecediiig «i)eeiiw poHse.ss tlii- fi-atui-es ii.siially recoj>:iiizo<l lus chtu-actcM istic of the 

 g«iiUH CiLKTirrKS, but which ii»!vertholL'.ss appear to be (•(imiiioii to the genus MoNoriivrA of Ulrich. In the 

 present Htate of our knowletlge I pi-opose to leave them, a.s originally described, under the g-enus Ch«tetk8. 



CHiETETES (MoNOTRYPELLA) ARBUSCULUS. 



PLATK IX, FIGS. 1-3, i>-8, (4, 5) ? 



ChateU* frutiounui. Hall. Thirty-second Rept. N. Y. State Mus. Nat. IIL-^t., p. 148. 1879. 

 Not C/kbI'Uji /riitiro.iiig. Hai.i,. Ilhistrations of Devonian Fo-ssiLs, pi. 38, tigs. 1-5. 1876. 

 ClKttthitfnitUoMUji.WKU.. Report of State (ieologist for 1882. Kxj)!. pi. 9, figs. 1-8. 1883. 



CoRALLUM fruticose, several stems arising from a single base ; bifurcations 

 frequent ; l>ranches generally diverging at an angle of about forty-five 

 degrees ; diameter from 2 to 3 mm. Cell tubes polygonal, arising from the 

 center of the branch and very gnidually diverging to the surface ; walls 

 thin ; exterior smooth or slightly wrinkled transversely. Length of tubules 



