34 PKOCEEDINGS OP THE NATIONAL MUSEUM TOu 72 



PALMATOLEPIS PERLOBATUS Ulrich and Sassier 



Plate 11, figs. 16-19 



1926. Palmatolepis perloMtus Ulbich and Basslee, Proc. U. S. Nat Mus., 

 vol. 68, p. 49, pi. 7, figs. 19-23. 



Plate irregularly diamond shaped, flexed either to the right or to 

 the left in the posterior portion. The ridge extends the whole length 

 of the plate and is slightly produced beyond by a short, thick carina. 

 The anterior portion of the ridge is indicated by a low, narrow line. 

 From a central prominence the ridge thickens toward the carina. 

 One side, which is rounded, extends slightly beyond the center. The 

 other side which is produced in the central region by an angular lobe 

 extends almost the entire length of the median ridge but becomes 

 gradually narrower as it approaches the carina. In the anterior 

 lobe the short, blunt tubercules converge toward the central prom- 

 inence. This in the posterior half of the plate are at right angles 

 to the central ridge. 



Plesiotype.— Cat. No. 11, 463, U.S.N.M. 



EXPLANATION OF PLATES 

 Plates 1 



All of the figures on this and the following seven plates are copied from the 

 authors cited. The magnification was often not stated but it lies usually 

 Ibetween 10 and 20 diameters. 



Fig. 1. Distacodus (Machairodus) angustus Pander, 1856. 



2. Distacodus {Machairodus) canaliculatus Pander, 1856. 



3, 4. Distacodus (Machairodus) dilatatus Pander, 1856. 

 5-9. Distacodus (Machairodus) etisiformis Pander, 1856. 



10. Distacodus (Machairodus) inaequalis Pander, 1856, 



11. Distacodus (Machairodus) incurvus Pander, 1856. 



12. Distacodus incurvus (Pander) Hinde, 1879. 



13. Distacodus (Machairodus) planus Pander, 1856. 



14. Distacodus (Machairodia) rhombeus (Pander) Smith, 1907. 



15. Distacodus (Machairodia) sulcata Smith, 1907. 



16. Belodus gracilis Pander, 1856. 



17. Distacodus (Machairodus) rhomboideus Pander, 1856. 



18. Distacodus (Machairodus) rhomboideus Pander, 1856, var. 



19. Distacodus (Machairodus) solidus Pander, 1856. 



20. Acodus acutus Pander, 1856. 



21. 22, Acodus crassus Pander, 1856. 



23. Acodus erectus Pander, 1856. 



24. Acodus planus Pander, 1856. 



25. Acodus sigmoideus Pander, 1856. 



26. Acontiodus gracilis Pander, 1856. 



27. Acontiodus latus Pander, 1956. 



28. Acontiodus triangularis Pander, 1856. 



29. Drepanodus acutus Pander, 1856. 

 30-35. Drepanodus arcuatus Pander, 1856. 



36,37. Drepanodus arcuatus (Pander) Hinde, 1879. 

 38. Drepanodus falcatus Hadding, 1913. 

 39-41. Drepanodus fiexuosus Pander, 1856. 

 42, Drepanodus i/nflexus Pander, 1856, 



