146 



Bryozoans of the 



Many of the species known in New York likewise occur in Canada; 

 and furtlier collections will donbtless show that nearly all are common 

 to the two regions. 



In the more calcareous portions of the formation, the determination 

 of specific characters is attended Avith great difficulty, and many still 

 remain for future study and decision. 



The Hamilton Group, in nearly its entire extent, has furnished 

 numerous Bryozoans of varied and interesting forms ; which will be 

 given in full in the State Museum Reports : the space allotted to this 

 communication admitting^ onlvsuch as have been studied and arranged 

 to precede the Fenestellidje. The descriptions of the latter are 

 however completed, and in the hands of the printer. 



In the determination of all these forms, as well as in their illustra- 

 tion in numerous excellent figures, I have been greatly indebted to 

 Mr. George B. Simpson, except for whose zeal in the study and 

 careful discrimination of the specific forms, I should, amidst other 

 duties, have left, for the present at least, many of them undetermined 

 and undescribed. 



OH^TETES, Fisclier. 



CHyETETES CEEBRIEAMA, U. Sp. 



Coral ramose, solid; branches frequent, bifurcating, occasionally tri- 

 furcating; cells tubular, polygonal, gradually diverging till within .75 

 mm. of the surface, when they turn more abruptly, opening slightly 

 oblique, diameter at aperture .25 mm., in the interior walls thin, at the 

 surface thickened, the thickness of the walls frequently equal to the 

 diameter of an aperture ; tubes septate ; septa very thin and fragile, 

 occurring at irregular intervals; on the surface are maculae distant 

 from each other from 2.5 mm. to 3 mm., which are sometimes elevated. 

 The maculse form a prominent feature of the branches. 



Locality — Falls of the Ohio river, near Lo^iisville, Ky. 



CHtETETES ^EQUIDISTAXS, U. 82^. 



Ramose, solid ; branches infrequent, diameter 5 mm. ; cells tubular, 

 polygonal, septate; septa strong, near the surface there are four in the 

 space of one mm., in the remaining portion from eleven to thirteen, 

 equidistant ; cell-tubes 8 mm. in length, apertures oval, length 5 mm., 

 with spinules at the angles, surface with maculse of large cell-apertures. 



Locality — Xew York. 



ClI.ETETES EGEXUS, 11. Sp, 



Ramose; branches infrequent, diameter 5 mm.; cells tubular poly- 

 gonal, non-septate, walls very thin; apertures very irregular in size 



