MOKOGKAPH OF THE EXISTING CRINOIDS. 769 



Fig. 1325. — Radial pentagon of Antedon hifida after removal of dorsal surface in such a way as 

 to lay open the radiating axial canals and their intercommunicating branches; 

 around central space is irregular calcareous networli formed by inosculation of 

 processes sent ofif from Internal fiices of the nidials. (After W. B. Carpenter.) 



Plate 48. 



Fig. 1326. — Ventral muscle pairs of a young specimen of Antedon bifida. (After W. B. Carpen- 

 ter.) 

 1327.^Proximal portion of arm pair with the lower pinnules of specimen of Antedon bifida 

 with soft parts removed, showing disposition of ventral muscles. (After W. B. 

 Carpenter.) 



Plate 49. 



Fio. 1328. — Tip and central portion of pinnule of Isometra viiipara, showing side and covering 

 plates. 

 1329. — Side and covering plates along ambulacral furrow of arm of Notocrinus virilis; the 



irregular dark median area represents furrow. 

 1330. — Tip and central portion of a pinnule of Notocrinus virUis, showing the side and cov- 

 ering plates. 

 1331. — Spicules of the tentacles of Isometra viiipara. (After Mortensen.) 



Plate 50. 



Fig. 1332. — Dorsal view of specimen of Comatulella brachiolata ; the stout pinnules with their 

 tips coiled dorsally are ungrooved ; the much more slender pinnules alternating with 

 them are grooved. 



1333. — Specimen of Antedon bifida with regenerating postradial series and IIBr axillary 

 bearing two arms growing upon the first brachials of the original single arm, 

 which has been broken off at the synarthry between the first two brachials. (After 

 W. B. Cari>enter.) 



1334. — Fragments of arms of Antedon bifida from near their termination, showing the elon- 

 gate and almost cylindrical brachials. (After W. B. Carpenter.) 



1335. — Skeleton of basal portions of arms of mature pentacrinold of Antedon bifida, show- 

 ing the very slightly developed perisomic plates, (.\fter W. B. Carpenter.) 



1336. — Vertical longitudinal section of an arm of Antedon hifida from near its base, show- 

 ing arrangement of muscles and ligaments and interruption of these at syzygy. 

 (After W. B. Carpenter.) 



Plate 51. 



Fio. 1337. — Si.xteen jjentacrinoids of Antedon mediterranea attached to the stem of Fucus, sp. 

 from Naples. X 4. 

 1338. — Pentacrinold of Antedon mediterranea, from Naples. X 4. 

 1339. — Pentacrinold of Antedon mediterranea, from Naples. X 4. 

 1340. — Pentacrinold of Antedon mediterranea, from Naples. X 4. 



Plate 52. 



Fio. 1341. — Specimen of CapillaUer seniosa from Singapore to which Is attached an Ophinmaza. 



Natural size. 

 1342. — Portion of the column of the type specimen of Metacrinus baiheri from the Malay 



Archipelago, 160 fathoms, upon which is growing a parasitic hydrold. Natural 



size. 

 1343. — Miizoatomum filiferwn. (After von Graff.) 

 1344. — iliizoxtomuiii quadricaudntiim. (After von Graff.) 



