20 The Paleontologist. [Jan. 15, 



GENUS CHAETETES. (Fischer.) 



Chaetetes minutus. (sp. nov.) (James.) {minutus — small.) 



Corallum (the parts observed) consisting of very small, cylindrical, branch- 

 ing stems. Perfect examples show sharp spines on the upper edges of the 

 thin walls of the corallites, which have an upward oblique direction, as shown 

 by a longitudinal section ; the central part of the stem is very compact — in- 

 ternal structure not made out under a good magnifier. Calices variable in 

 size and shape, from sub-circular to long oval, sometimes much drav n out, 

 and in some cases seemingly confluent. About 10 or 12 calices in the space 

 of a line measuring longitudinally — their longer diameter — but much smaller, 

 generally, in a transverse direction. 



Examples, so far observed, measure from 2 to 4 lines in length and from y^ 

 to ^ a line in diameter. 



Found near Loveland, Clermont Co., O , Cincinnati Group. 



Chaetetes crustulatUS. (James ) fsp.) Paleontologist No. I, July, 1878. 



In the original description of this species it is stated that it has " no surface 

 prominences of any kind." Since that time I have seen examples with slight 

 elevations, elongated longitudinally, but having all the other characteristic 

 features of the typical form. 



I have also discovered, what was not then apparent, in a number of undeter- 

 mined specimens, other features of the species, consisting of parallel lines 

 about yk of a line apart, with connecting walls, at various angles about the 

 same space apart. The lines are sometimes straight, others curved or tortuous. 

 These lines are at the bases or central axis of the corallites. Of this I have 

 positive evidence in cases wliere the coral has divided — partly scaled off — 

 showing both base, or interior and outer surface structure in the same indkndual 

 example. The parallel lines and connecting walls are sometimes raised and 

 sharp, thread-like in appearance, showing the foundation (laid off in outline) 

 of the corallum ; in other cases they are even with the surface snowing through 

 what may be an exceedingly delicate, thin epitheca. Altogether these are very 

 interesting features of the species. 



Chaetetes lycopodites. (sp.) (Vanuxem.) Not Chaetetes lycoperdon, Say. 



In the second number (Sept. 15) of the Paleontologist we made some re- 

 marks on the above named fossil species. Since that date Dr. C. A. White, 

 U. S. Paleontologist, has kindly furnished the following facts in regard to its 

 history, which we are permitted to publish : 



"The Lower Silurian fossil that has become generally known as Chaetetes 

 lycoperdon and attributed to Say, was never published by him by that name, 

 nor by any other. The late T. A. Conrad, in a private letter, informed me 

 that Say, before his death, placed a specimen of that fossil in the cabinet of 

 the Acad Nat. Sci , Phila. labeled "-Chaetetes lycoperdon'' where it remained 

 for several years. This name was first published by Prof. Hall in Vol. i. Pal. 

 New York in 1847, where it attributed the name to Say, but does not refer to 

 it as Say's M. S. name That species was first published by Vanuxem as 

 Favosites lycopodites in his report on the Geology of the 3d district of New 

 York, p. 46, 1842, where he also gave a good figure of it. The specific name is 

 therefore Vanuxem's, and ought to be written Chaetetes lycopodites,Y annxem sp." 



GENUS PTILODICTYA, (Lonsdale.) 



Ptilodictya nodosa, ^sp. nov.) (James.) {nodosa— knotty.) 

 Polyzoary consisting of a flattened, straight, unbranched frond, with a 

 pointed base, expanding upward to a width of 5 or 6 lines ; length i }4 inches. 

 The base is finely striated to the height of about i y lines, bearing very small 

 elongated pores between the striae; above, for a space of about 2 lines more, 

 there are two parallel lines close together, and between each two series of 



