PLATE XXV. 



Calymene platys. 



Page 1. 

 See Plate 1. 

 ], \n . xii.Mii.'K large pygidium, retaining, onb/, a sinall portion of the crust. Accompanying this is 

 -111 outline restoration drawn upon the basis of this pygidium, to indicate the dimensions the 

 animal maj have attained when entire. Normally the pygidium of the animal is somewhat 

 incurved, as shown in tig. 2. In this drawing the pygidium is viewed from behind, ami not 

 from above, appearing therefore detached from the restored thorax. 

 Corniferous limestone. Falls of tlu Ohio. 

 I _ 2. A large, somewhat imperfect individual, retaining the parts' iri juxtaposition. 

 Upper Helderberg limestone. HagersviU'e, Prov'i nre of Ontario. 



\ ? | Phacops 1IANA. 



Page 19. 

 See Plates 7, 8 and Sa. 

 Fig. ::. A cephalon from which the crust has been removed : showing the glabellar furrows, the deep and 

 broad occipital furrow, made more conspicuous by the obsolescence of the third or basal lobes. 

 I .■... 4. A profile view of the same, showing the somewhat protuberant and slightly flattened glabella, 

 the subangulate genal extremities and the elevated occipital ring. 

 This specimen is from the Eureka District, Nevada, and shows a close relationship to Phacops 

 cristata in the broad and deep occipital furrow and other features. (See page 25.) 



LlCHAS (HOPLOLICHAS) HYLvEUS. 



Page 81. 



See Plate 19 b. 



Pip., :,. An in postoma, found in association with the cephalon of this species. Enlarged to two diameters. 



Upper Helderberg limestone. North Cayuga, Prmrince'bf Onitarvol 



Proetus DELPHINULUS. 



Page 111. 

 See Plate 23. 

 Fig. 6. The cephalon represented on plate 2ii. figs. 1 and 2: drawn from a gutta percha impression from 

 a natural mould of the dorsal surface, showing the character of the glabellar lobes and fur- 

 rows. Enlarged to three diameters. 



Proetus jejunus. 



Page 124. 

 Fig. 7. The pygidium enlarged to two diameters; showing the axial row of nodes and the broad pleura? 

 with their bifurcate annulations. 



Hamilton group. Albany county. 



Proetus crassimarginatus. 



Page 99. 

 See Plates 20 and 22. 

 Fig. 8. The axis of the pygidium enlarged to two diameters. The internal cavity of the axis has been 

 tilled with I ii nt calcite. and by the removal of the outer portion of the test, the position 



and character of the muscular sears upon the lower surface are very distinctly shown, 

 liferous limestone. Falls of tlu Ohio. 



