LECAN0CR1NIDAE 1 97 



tion. Sutures between RR and IBr and succeeding plates beveled. Anal x 

 small, filling the interradius. Column unknown, facet small. 



This species when first recognized was represented by a single specimen, found by 

 Dr. Carl Rominger in the Knobstone formation at Button Mould Knob, Bullitt County, Ken- 

 tucky, and presented to me by him the year before his death ; but it has been recently con- 

 firmed by another specimen from the same locality. It is a typical Mespilocrinus, with the 

 unsymmetric and unequal radial and brachial plates, and twist of the rays. Except for its 

 beveled sutures and smaller anal, which may be more apparent than real depending on the 

 folding of the rays, this form would be difficult to separate from M. konincki if found in the 

 same matrix at Burlington. From the other Knobstone species it is distinguished without 

 difficulty, being of an altogether different type. 



The species is dedicated to the memory of Dr. Carl Rominger, the veteran geologist and 

 paleontologist of Michigan University, from whom I received the principal type specimen. 



Types. Author's collection. 



Horizon and locality. Lower Carboniferous, Knobstone Group ; Button Mould Knob, 

 Kentucky. 



Mespilocrinus bordeni n. sp. 



Plate V , figs. 2ja-c 



A large species. Crown subovoid, broadly rounded above, narrower below ; 

 20 mm. high by 20 mm. wide; widest to top of RR, where height to width 

 is 1 to 1.5 ; spread of calyx from base to top of RR, 1 to 3 ; base small. 



IBB small. BB large. RR large with facets straight. IBr 2, very short 

 and wide, less than one-fourth the length of radials, and one-fourth as long as 

 wide. B to R to IBr, 9:7:1.5. IIBr 6 or 7, very short, decreasing rapidly in 

 width upward. Rays and arms flat, in close contact, infolding about the second 

 bifurcation. Column large proximally, facet almost as large as IBB ; unknown 

 farther down. Anal side unknown. 



The distorted specimen upon which this species is founded was given to me by the' late 

 Professor W. W. Borden, who personally collected it during his later years from the Knob- 

 stone beds at one of the knobs near Borden, Clark Co., Indiana. It was associated with some 

 other rare crinoids, among them Wachsnutthicrinus spinosulus, from thin layers of clay, and 

 all much flattened. Part of the crown is broken away, unfortunately including the anal side. 

 Three of the rays and the base are in good condition, and from these I have made an accurate 

 restoration, showing the undistorted form and correct proportions of the specimen (PI. V, 

 fig. 23c). 



This species is in some respects very different from any of the others, and it is quite 

 possible that if the anal side were known it would fall into another genus. The extremely 

 short and wide interlocking brachials, and the unusual number of secundibrachs, give to it a 

 facies quite peculiar. In other species the secundibrachs are generally two, with sometimes 

 three, whereas the six or seven found here would be extraordinary even for Lecanocrinus, 

 which the short brachials recall. These differences of course do not of themselves indicate 

 another genus, but they induce a strong desire to see a complete specimen. This form appar- 

 ently lacks the asymmetry and dextrorse twist of the rays characteristic of typical species. 

 The genus is represented in the same beds by another species which is not at all like this. 



The specific name is in memory of Professor W. W. Borde'n, of Borden, Indiana ; a 

 pioneer geologist, who died in December, 1906, at the advanced age of 80 years. An ardent 



