100 [Apri2^ 



1 



CLIMAXODUS McCoy. 



C. BEEVis Newb. Teeth oval, in form, shorter than C imhricaius McCoj. 

 Eidges which cross- the surface more remote, with sharp crests and sinuous out- 

 line. 



PLEURACANTHUS Agass. 



P. BiSERiALis Newb. Spine straight, strong, tapering rapidly to a moderately 

 acute termination. Length four inches ; diameter at base 4 lines. Anterior 

 face rounded ; posterior face nearly flat. Entire surface finely striated longitu- 

 dinally. Sides flattened, joining posterior surface at right angles. At angle oa 

 each side a double row of small, closely set, acuminate, depressed hooks. On 

 the ujiper part of the spine the hooks are arranged in a single row. Side of spine 

 at base of the hooks marked by a distinct longitudinal furrow. 



P. ARCUATUS Newb. Spine slightly curved backward, rapidly tapering to an 

 acute point. Anterior surface rounded ; posterior face nearly flat. At angle 

 formed by the junction of sides with posterior face is, on each side, a single row 

 of closely set, acuminatCj depressed hooks. Anterior surface marked with fine 

 longitudinal striae. 



P. DILATATUS Ncwb. Spine short, robust, one inch- six lines long, straight, 

 acuminate at summit, largest nar middle, contracted at base; Anterior face 

 rounded ; posterior face flattened, and bearing at the angles on either side a 

 row of minute depressed hooks. Surface smooth. 



COMPSACANTHUS Newb. 



Spines of small size-, very neat in form and finish. Section at all points cir- 

 cular. A single row of relatively large, remote, depressed hooks it set along ths 

 posterior median line. 



Of this genus I have probably but one species. 



C. LJJvis Newb. Spine slender, curved, acuminate, having a circular section 

 at all points ; upper two-thirds furnished with a single row of depressed acumi- 

 nated hooks remotely set along median line of posterior surface. 



On motion of Mr. Cassin, a Committee was appointed to prepare a 

 list of Correspondents for publication. The following compose the 

 Committae : Mr. Cassia; Dr. Le Coate and Dr. Leidy. 



ELECTION. 



Dr. R. A. Penrose and Mr. Wm. H. Patterson, of Philadelphia, wer- 

 elected Members, and Mr. P. B. Meek, of Albany, was ekcted a Coi-res- 

 jjondent. 



