KXPLANATION OF PLATE LVI. 



Phi)LaD(imva iicciiien'i'alis Morton ii. 513 



1-3. Antcriijr, lateral ami cardinal \'ie\\'> of a ncarl_v C"m])lctc 

 internal cast. 



M cichdiilviUc ihiy-inarl: I.cnula. ( ;6_? ) . 



Piioi, AD(m^•A koe-Mi;ki W'liilliclJ P- 515 



4, Lateral \ie\v r.f ihe tj'pe specimen. 



ll'ctuiiHih mild: near Marlboro. 



5. Lateral \ie\v of .1 smaller incli\-idual. 



Il'ciioiiiih stiiiJ : iicor Mai'lhoro, (130). 



Crenet.la Ei.EC.\XTri..\ ileek anel 1 layden p. 511 



0. I^ateral view of an internal cast. 



'J'iiiloii beds: Boors llill (.^iil. U-'f/'). 



Crexeei. A SEi;ic.\ Cimrad p. 510 



y~S. Lateral \"ie\\s of Iwn sm,ti"le A'ah'es. ( X2 ) . 



.Marsliiillt<izoii olay-iiiai-l ; iioar Sioodosboro, (lyy). 



LiTiioPH.\G.\ Ripr.EV.VNW ( Gabli ) p. 512 



g-io. Lateral and cardinal A'iews of a rather smooth example. 



Xaz'osiiiL' marl; MiiHioa Hill, {i6g}. 

 Ii~i2. Lateral anel cardinal views iif a rouglier example. 

 AhToosiiik mail: iioar H'ahilord, (i-iS). 



Cekcomva I'ECLXaris (Conrad ) p. 518 



13-14. Two views of the lype specimen. (After Whuheld.) 

 Xai'osuil: iiiai'l: Crossioioks Crook. 



994 



