364 CALIFORNIA ACADEMY OF SCIENCES. 



Elymocaris Beecher, 1884; 2d Geol. Survey Penn., vol. PPP., p. 13. 



Devonian. 

 Tropidocaris Beecher, 1884; 2d Geol. Kep. Penn., vol. PPP, p. 15. 



Wrinkled. Devonian. 



Ptychocari.s Novak, 1885; Sitzungsb. bohm. Gesell., 1885, p. 343. 



Wrinkled. Silurian. 



Phasganocaris Novak, 1886; Sitzungsb. bohm. Gesell., 1886, p. 498. 



Only telson known. Silurian. 



IV. With swellings in the antero-ventral region; ocular tubercle not 



apparent. 

 Callizoe Barr., 1872; Syst. Sil. Boheme, vol. 1, suppl., p. 503. Leper- 

 ditoid. Silurian. 



V. Conchiferoidal. 



LiNGULOCARis Salt., 1866; Mem. Geol. Survey, vol. 3, pp. 252, 253, and 294. 



Modioloid, and faintly ridged. Tremadoc. 



Steigocaris Vogd., 1889. Pod-shaped and concentrically marked. 



Carboniferous. 

 SoLENOCARis Young, 1868; Proc. Nat. Hist. Soc. Glasgow, vol. 1, p. 171. 

 ? Orthonotella Ulrich, 1882. Oblong. Silurian. 



Myocaris Salt., 1864; Quart. Jour. Geol. Soc. London, vol. 20, 1864, p. 292. 



Quadrangular and ridged obliquely. Silurian or Devonian. 



PiNACARIDiE. 



Mesothyra Hall, 1888; Palteont. New York, vol. 7, pp. Ivi, 187. Hamilton 

 and Portage formations. 



RHINOCARID.aC. 



Rhinocaris Clarke, 1888; Palseont. New York, vol. 7, p. Iviii. Anterior 

 extremity of the head produced into a point. Devonian. 



Not Classified. 

 Protocaris Wal., 1885; Bull. U. S. Geol. Survey, No. 10, p. 50. Taconic. 

 Anomalocaris Whiteaves, 1892; Canadian Eec. Sci., vol. 5, p. 205. 



Taconic. 

 RoSTROCARis Kinnear, 1887; Trans. Edinb. Geol. Soc, vol. 5, p. 417. 

 ARCHiEOCARis Meek, 1871; Proc. Acad. Nat. Sci. Phila., p. 3.35. 



Carboniferous. 

 DiCTYOCARis Salt., 1860; Annals Mag. Nat. Hist. London, 3d series, vol. 3, 



p. 101. 

 AcANTHoCARis Peach, 1882; Trans. Royal Soc. Edinb., vol. 30, p. 511. 



PHYLLOPODA. 

 Leaia Jones, 1882; Mon. Fossil Estheria, p. 115. Quadrangular, ridged 



obliquely, and concentrically marked. Carboniferous. 



Estheria Riippell, 1857; Mus. Senckenberg, vol. 2, p. 119. Likeabivalved 



mollusc and concentrically marked. Devonian. Carboniferous. 



Triassic. Rhastic. Jurassic. Cretaceous. Tertiary — Recent. 

 EsTHERiELLA Weiss, 1875; Zeitsch. Geol. Gesell. Berlin, vol. 27, p. 711. 

 ScHizoDiscus Clarke, 1888; Palaeout. New York, vol. 7, p. 207. Devonian. 



