MEYERIA. 33 



Meteria oknata, sp., Phillijjs. Plate IX, figs. 9 — 1 1 . 



Seginentis abdominis seriebus quatuor vel quinque transversis granonim ornatis ; pro- 

 cessibus lateralibus granulatis. 



AsTACUS OKNATUS, PMll. Geol. York, t. iii, fig. 2. 



Meyeria ornata, M'Coy. Ann. Nat. Hist., 1849, p. 333 ; Contrib. to Brit. Palseont.. 



p. 138. 

 — — Morris. Cat. Brit. Foss., p. 111. 



Bescr. Carapace scabrous, with even, sharp granulations ; the portion anterior to the 

 nuchal furrow (the cephalic arch) with three or four denticulated carina3 ; the nuchal 

 furrow deep, forming an acute angle on the mesial line of the back. The portion behind 

 the furrow (the scapular arch) much larger than the former, compressed, scabrous, with 

 rather distant granulations. The abdomen is semi-cylindrical ; each segment ornamented 

 with four or five transverse, elevated rows of very distinct, rounded granulations, and 

 similar ones are scattered over the epimeral plates, which are moderately large, those of 

 the first and second segment broad and imperfec^y quadrilateral, the remainder trigonal. 

 The tail is rather short, the central plate rounded at the extremity, sulcated, and granu- 

 lated ; the exterior plate is slightly curved, and has a longitudinal carina and furrow and 

 a row of granulations. 



Length of the carapace 1*3 inch, length of abdomen 2 inches. 



This species has, I believe, been hitherto found only in the Speeton clay, where it 

 occurs in oval nodules. Specimens exist in the British Museum, in the Woodwardian at 

 Cambridge, the York Museum, and in Dr. Bowerbank's and other private collections. 



Meyeria vectensis. Plate X. 



Segmentis abdominis longitudinaliter tricarinatis ; carinis granulatis. 



Myeria magna, M'Coy. Ann. Nat. Hist., 18-19, p. 334 ; Contrib. Brit. Palseont., 



p. 139. 

 — — Morris. Cat. Brit, Foss., p. 1 11. 



Bescr. The carapace in this species is very deep, much compressed, the lower part of 

 the sides being nearly perpendicular ; the nuchal furrow is deep, and its angle is less acute 

 than in M. ornata ; the cephalic portion is gradually narrowed forwards, terminated by 

 a short, slender, acute rostrum, which is not more than one fourth the length of the 



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