ABT. 9 NEW CAMBEIAN CKUSTACEA — EESSER 15 



DESCRIPTION OF PLATES " 



Plate 1 Page 



Tuzoia redfera Walcott 7 



Fig. 1. Left valve retaining the three large rear spines. In this specimen 

 the keel was pressed down toward the lower margin, giving it 

 a more curved shape and a more ventral position than it had 

 in a perpendicular view of the undistorted shell and thereby the 

 reticulations have been almost obliterated in the crushed portions 

 and nearly effaced in places beyond this area. A specimen of 

 the abundant gastropod, Scenella varians, projects through the 

 shell near its lower margin. Plesiotype, Cat. No. 80484, 

 U.S.N.M. 

 2. A new photograph of the original holotype figured by Walcott. 

 In this specimen the larger marginal spines are apparently 

 broken off. The keel is pressed almost vertically downward, 

 thereby causing but little distortion on any part of the shell 

 except near the front end where the reticulations show crowd- 

 ing. An examination of the margin indicates that both valves 

 are present. Holotype, Cat. No. 57720, U.S.N.M. 



Middle Cambrian, Burgess shale; (loc. 35k) near Field, 

 British Columbia. 



Plate 2 



Tuzoia burgessensis, new species 8 



Fig. 1. A well preserved specimen with the left valve uppermost. In the 



flattening the keel was crushed down directly to the rear. Note 



the three strong marginal spines and the rather regular smaller 



spines along the remainder of the outer margin; also the absence 



of intermediate spines. Several of the blunt spines along the 



dorsal line can be seen. Holotype, Cat. No. 80477, U.S.N.M. 



Middle Cambrian, Burgess shale; (loc. 35k) near Field, 



British Columbia. 



Tuzoia canadensis, new species 8 



2. Cast of exterior of rear portion of left valve, showing the four 



large posterior spines. Some of the smaller more regular 

 spines are visible forward along the lower margin. Paratype, 

 Cat. No. 80478, U.S.N.M. 



3. Major portion of right valve. Several intermediate marginal 



spines are visible anterior to the fourth large posterior spine. 

 Holotype, Cat. No. 80478, U.S.N.M. 



Middle Cambrian, Burgess shale; (loc. 35k) near Field, 

 British Columbia. 

 Anomalocaris cranbrookensis, new species 12 



4. Usual lateral view of this animal. Twelve or thriteen segments 



anterior to the bifiurcated caudal division. Somites and ap- 

 pendages may not be quite correctly outlined as specimen is 

 little distinct from matrix. Holotype, Cat. No. 80479, U.S.N.M. 

 Lower Cambrian, Eager formation; (loc. 67g) near Cran- 

 brook, British Columbia. 

 Roddyia typa, new species f 14 



5. Dorsal view of cephalic shield (X2). Holotype, Cat. No. 80480, 



U.S.N.M. 



Lower Cambrian, Kinzers formation; (loc. 12x) near 

 Rohrerstown, Pennsylvania. 



"All figures are natural size unlesa otherwise indicated. 



