658 



ARTHROPODA 



SUB -KINGDOM VII 



Family 1. Discinocaridae. Woodward. 

 Test convex, sometimes mesially ridged ; in a single piece. 



Discinocaris, Woodw. Shield sub-circular, rostral notch, and rostrum angular. 

 Abdominal segments and caudal spines have been referred to this 

 genus by Jones and Woodward. Silurian; Great Britain, 

 Bohemia. 



Aspidocaris, Eeuss. Similar to Discinocaris. Raibl Beds 

 (Trias); Hallstadt. 



Dipterocaris, Clarke (Fig. 1378). Shield with a deep posterior 

 notch, shorter than the anterior or rostral notch. Sides of shield 

 sloping. Silurian ; Scotland. Upper Devonian ; New York. 



FIG. 1378. 



Dipterocaris vetustus, 

 d'Arch. and Vern. De- 

 vonian ; Eifel. 1/1- 



Salter. 



notch and plate. 



FIG. 1379. 



Aptychopsis primus, 

 Barr. Ordovician (D) ; 



Family 2. Peltocaridae. 



Shields mesially sutured. 



Peltocaris, Salter. Circular shields with a rounded rostral 

 Abdomen unknown. Ordovician ; Great Britain. 



Aptychopsis, Barr. (Fig. 1379). Like Peltocaris, but with the 

 rostral notch angular. Silurian ; Bohemia and Great Britain. 



Pinnocaris, Etheridge. Similar to Dipterocaris, but bivalved. 

 Ordovician ; Scotland. (P. Lapworthi, Etheridge jun.) 



Addendum. 



A number of generic names, such as Gardiocaris (Fig. 1380), 

 Ellipsocaris, Pholadocaris, Woodward, and Spathiocaris, Clarke, 

 have been applied to Devonian fossils which closely resemble the Silurian Discinocaris, 

 of whose Crustacean nature there seems to be no doubt. Some of 

 these bodies, however (Cardiocaris), have been found in the living 

 chamber of Goniatites (G. intumescens), and have undoubtedly 

 served as opercula or aptychi of these Cephalopods ; of others 

 the nature is not fully understood. Lisgocaris, Clarke, is not a 

 Crustacean ; Cryptocaris, Barrande, is probably the operculum of 

 a Hyolithoid ; Myocaris, Salter, is stated to be a Pelecypod ; 

 Proricaris, Baily, was founded on parts of Ceratiocaris; Grescen- 

 tilla and Pterocaris, Barrande, are doubtfully Crustacean. 



FIG. 1380. 

 Cardiocaris (At 



ipty- 



. > w -, [The authorship of the foregoing chapters on Phyllopoda, Cirripedia, 



Upper W D?von fan'; and Phyllocarida, as well as the succeeding one on the Acerata (Mero- 

 Budesheim, Eifel. Vi- ' stomata), should be accredited to Dr. John M. Clarke, New York State 

 Palaeontologist. A number of additional figures for illustrating these 

 sections have also been prepared by him expressly for this work, or borrowed from his 

 previous writings. TRANS.] 



Order 2. SCHIZOPODA. Latreille. 1 



Small, elongated, aquatic Malacostraca with compound eyes borne on movable stalks, 

 and a large delicate carapace covering the thoracic segments more or less completely ; with 



1 Literature: 



Jordan, H., and Meyer, H. v., Crustaceen der Steinkohlenformation von Saarbriicken (Palaeontogr., 

 IV.), 1856. Salter, J. W., Higher Crustacea from British Coal Measures (Quar. Journ. Geol. Soc., 

 XVII.), 1861. Ethe,ridge, R., Occurrence of Anthrapalaemon in Carboniferous of Scotland (ibid. 

 XXXIII.), l877. Whitfteld, R. P., New Crustacea from the Devonian of Ohio (Amer. Journ. Sci. 

 [3], XIX.), 1880. Also in Ann. N.Y. Acad. Sci., V., 1891. Peach, B. N., New Crustacea from the 

 Carboniferous of Eskdale (Trans. Roy. Soc., Edinburgh, XXX., pp. 73, 512), 1880. Brocchi, P., 

 Note sur un Crustace, etc. (Bull. Soc. Geol. France [3], VIII.), 1880. Packard, A. S., On the 



