562 
PLATE XLVIII. 
Fic. 1. CosMACANTHUS PRISCUS, Agass., . . : : : . : 
Longitudinal section along centre of a spine. 
Mountain Limestone, Armagh, . Bx, coll. Geological Society of London. 
Fic. 2. Cosmacayruus priscus, Agass. External aspect of figure 1, : : ; 
» 2a. Transverse section of the same. 
Mountain Limestone, Armagh, . Ex coll. Geological Society of London. 
Fic. 3. CosMACANTHUS MARGINALIS, Davis, : 0 . ° e . 
» 3a. Transverse section of the same, near base. 
Mountain Limestone, Armagh, ; Ex coll. Enniskillen Collection, 
Fig. 4. CosMACANTHUS CARINATUS, Davis, 5 o 6 ° ° : 
Carboniferous Limestone, Armagh, . Ex coll. Enniskillen Collection. 
Fic. 5, LisPACANTHUS RETROGRADUS, Davis, : 6 : . ° : 
» 5a. Transverse section of the same. 
Limestone, Armagh, : : Ex coll. Enniskillen Collection. 
Fic. 6. LISPACANTHUS GRACILIS, Davis, . ; ; : 0 5 : 
Mt. Timestone, Kendal Fells, 3 . 
; > ; ; . Ex coll, Geological Society of London. 
Westmoreland. : 
Fics. 7-9. Homacantuus micropus, M‘Coy, , ° . . . : 
Fira. 8. HomaAcANTHUS MicroDus, M‘Coy, : : . : 6 . 
(Probably from the second dorsal fin). 
, 8a. Transverse section across the same spine. 
All from Mountain Limestone, Armagh, Ex coll. Enniskillen Collection. 
Fic. 10. Drprracanruus sToKest, M‘Coy, : , 5 ‘ 3 F 
, 10a. Enlarged portion of surface. 
Mt. Limestone, Armagh, Ex. coll. Woodwardian Museum, Cambridge. 
Fic. 11. GNATHACANTHUS TRIANGULARIS, Davis, . : 3 : ; P 
» lla. Portion of surface of same magnified. 
Mountain Limestone, Armagh, : He, coll. Enniskillen Collection, 
Vic. 12. GyarHacantuus striatus, Davis, ; ; ; : ; ; 
, 12a. Transverse section across the same. 
Mountain Limestone, Armagh, ; Ex. coll, Enniskillen Collection. 
Fig. 13. CHALAZACANTHUS VERRUCOSUS, Davis, . 5 ; d 6 : 
,, 13a. Transverse section across the same, midway towards the apex. 
13 b. Ditto, across the basal portion. 
Lower Carb. Limestone, Black Rock, Bristol, Ex. coll. Bristol Museum. 
or) 
Page 
358 
308 
359 
361 
361 
360 
363 
364 
371 
