80 • SAN DIEGO SOCIETY OF NATURAL HISTORY 



RAYMOND (Percy E) — Continued 



B. A group of species, in wliicli the second segment of the thorax is in no \vay 

 distinguishable from tlie otiiers. To tliis group belong the Scandinavian, British and 

 American forms. 



The author remarks that Paradoxidcs Ur.r'.ani, differs from other species and one 

 which makes it almost unique, in the wide, depressed brim at the anterior end of the 

 cranidium. 



New and old Silurian Ti'ilol>it<'s t'l-oni S. E. Wisconsin, with 



nc'trs on the i^enera of Tllaenidae. 



Bull Mus. Comp. Zoo]., vol. 60, 1916, No. 1. 



The author divides the lllaenoidae into two sections: 



I. lllaenoidae. 



Genera Illaenus, Thaleops, Dysplanus, Wossekia gen. nov. and Octillaenus, Bumas- 

 tinae, Genera Bumastus, Actinolobus, Illaenoides. 



I'nder Bumatus the author includes descriptions of tlie following species: 



Bumastus cunicnlus Hall, B. Niof^arcns'is Whitf., B. Dayi nov., B. dccipietis nov., 

 B.. tenuis nov., B. irisi^^nis Hall, B. ioxus, B. frraflonrrisis. 



M. & W. & B. ittdrtcrm'inc.tus Wale. 



Under Eichwald's genus Actinolobus, he refers a single pygidium as A clinnlohus 

 A mrr'icanus from Racine Dolomite. 



n. J.ichadidae — 1 he author refers \\'el!er's Dicrnnfipfltis nnsuta to Tro( liurus iiiisult). 



Odontopleuridae — Ceratocephala goniafa Warder, 1S38. 



Encrinuridae — Encrinurus reflexus nnv. 



The author refers to a ne\v species a pygidium of large size, with 8 pairs of ribs 

 on the lateral lobes, which he compares with other American species. 



Calymmenidae — The author enumerates the following species: 



Cnlymmene Xi/igarrnsis Hall, C hrrvirrps nov. for Hall's C. ISingnrcitsis, 28th Rep. 

 N. Y. State Cab. Nat. Hist., pi. 32, fig. 7-15. 



Calymmene celebra nov. for Hall's C. Ntagarensis, 20th Rep. N. \'. State Cab. Nat. 

 Hist., p. 334, based on the pygidium which has 4 pairs of narrow ribs without im- 

 passed line, that reach only one-half way to the margin. New genus Liocalymene, with 

 Vauxem's species Hemicrypturus Clinforii for its genotype. This form has a smooth 

 pygidium without ribs and a jointed axis, from the Clinton of New ^'ork. 



This genus should include the French and Spanish Silurian form described a.- 

 Calymmcne Aragoi by Rouault, which differs from C. Solteri described b\ the same 

 author in having 10-11 joints on the axis, and C. Arngo only 7. 



CJieirurus N'uigarcnis Hall. The author restricts this species to Hall's species from 

 Rochester, Pal. N. Y., vol. 2, p. 303, pi. 67, f^gs. 9-10. 



Raymond refers the Ceraurus tnsignis Hall, Pal. N. Y., vol. 2, 1852, p. 300, pi. 6a, 

 fig. 4, to Chcirurus JVcllrri nov. Also included Roemer's C. himucrnnntn Sil. Fauna, 

 Tenn., p. 80, pi. 5, fig. 19, and Hall's C. Nlagarensis. 20 Rep. N. Y. State Cab. Nat. 

 Hist., pi. 21, figs. 10-11, and others. 



Chfirurus dilatatus nov. for Hall's Spliofrcxochus Rom'rigcri? 28 Rep. N. Y. State 

 Mus. Nat. Hist., 1877, pi. 32, fig. 16. 



CJieirurus patens nov., C. Tarquinius Bill., C. Hydei Weller, and C. nuperus Bill. 



The type of this species was lost and no furtlier specimens have been described. 



Sphaerexochus Romingeri Hall. The author remarks that the pygidium of this 

 species is rare and usually incorrectly figured. The pygidium is entire, and the spine- 

 figured by Hail are tlie ribs on the pleural lobes. 



Becclicr's classification of Trilohitcs after twenty years. 



Am. Jour. Sci., ser. 4, vol. 43, 1917, p. 196-210. 



