NOTES ON GENERA. 125 



deniis — Staueandekasteh,' uox imi. 



Pentaciokos (pars). V[>. 7t)-S'.t of this Mouograj)li. 



The species hitlbij'enis, Bui/sli, coroiudns, oci'llatitfi, hispiiiosiis, iiistilli/crns, and 

 siiitninatiis (pp. 70 — 8'.* of this Monograph), which have been foriiierly phiced in the 

 genus I'lmtaccros, together with the new species anjus (p. U9), shouhl, I think, 

 now be ascribed to a new genus. The phites of these species are breast-phite- 

 shaped, at times ahnost cross-shaped, and l)ear a characteristic type of oi nanient 

 (see p. 113). In both these respects and in the absence of papidar areas the 

 species differ widely from species of recent Pevtuceros, with which the only feature 

 they have in common is the circlet of raised plates on the abactinal surface of the 

 disc. 



The type species of the new genus is Stauramleraster Dotjsii, and its diagnostic 

 characters are : 



Arms high, well produced, marginalia breast-plate-shaped, generally with a 

 rabbet-edge free from ornament, and a raised interior area, either smooth or with 

 ornament of an embossed type. A circlet of swollen plates present on the 

 aljactinal surface of the disc. 



This genus, with tlie following genus, may l)e placed provisionally in the family 

 Pentacerotidae. 



Genus — Hadkandebaster,- novum. 



Pentaci;i;os (par.s), p. 8G of this Monogi-aph. 



The species described as Pentaceros tibbreviatus on p. 80 of this Monograpii 

 differs so considerably in the shape of its marginalia and their ornament from the 

 species of Stauranderasler and recent species of L'cntacevos that I have placed it in 

 a now genus. 



The type species is HaJraitdcnititer abbrvciatiis, and the diagnostic characters 

 of the new genus are : 



Arms high, well produced, marginalia either hexagonal or rounded, very thick, 

 ornament spread imiformly over the surface of the plate. Pedicellaria l>i-valvate. 



* aravpoi = a croas, Hvitipov = a raised garden border. 

 ' dSpot = stout, nfSrjijOf = a raised garden border. 



19 



