730 • NEW YORK STATE MUSEUM 



Climacograptus pungens sp. nov. 



Plate 16, figures 14-20 



Climacograptus sp. nov. Ruedemann. N. T. State Paleontol. An. Eep't. 

 1902. p.571 



The finding of two small rhabdosomes, in the Deep kill shale with 

 Diplograptus dentatus, has proved the appearance of the genus 

 Climacograptus at this early date in this region. Later on, numerous 

 specimens of the form here described Avere found in a still somewhat older 

 subhorizon at Mt Moreno, near Hudson. As the only other species known 

 to occur so early, viz C. scharenbergi Lapworth [Ellergill beds of 

 England; see Elles, 1898, p.519j, is a distinctly different form, and the frag- 

 ments can not be readily assigned to any younger species, they are here 

 described as representing a new species. 



Description. Rhabdosome small (length of largest specimen 18 mm, 

 but average length only 12 mm) and narrow (1.6 in one case, as a rule not 

 over 1 . 3 mm wide), of uniform width. Sicular end provided with two very 

 long (12 mm or more), extremely slender and flexuous appendages. The 

 thecae are short, closely arranged, numbering 10 to 12 in 10 mm; the 

 apertures relatively large, broadly oval, provided at their outer margin with a 

 short spine [pi. 16, fig.l4j. The sutural groove is little distinct, slightly 

 undulating. The nemacaulus relatively stout and long. 



Position and localities. Rare in the horizon with Diplograptus 

 dentatus at the Deep kill ; common in the same horizon at Mt 

 Moreno. 



Remarles. From C . scharenbergi this form is readily distinguished 

 by the character of the sutural groove, which in that species is deep and 

 characteristically deflected from side to side, horizontal grooves setting out 

 from the outer points of each angulation. The long appendages and the 

 apertural spines are also a feature not observed in that species, which 

 besides, has a greater number of thecae within a space of 10 mm. 



