MONOGRAPH OF THE EXISTING CBINOIDS. 



229 



Challenger. In 1881 he described similar plates in Stylometra spinifera, and in 

 1884 in Thalassometra lusitanica. 



In his memoir on the stalked crinoids of the Challenger expedition published 

 in 1884 Carpenter wrote that the margins of the ambulacra of the disk, arms, 



Fios. 336-350. PINNULES or VARIOUS COMATULIDS. 336. MIDDLE PINNULES OF NBOMETRA MDLTICOLOE. 

 337. MIDDLE PINNULES OF STYLOMETRA SPINIFEHA. 338. MIDDLE PINNULES OF THALASSOMETRA 

 PCBESCENS. 339. DISTAL PINNULES OF NEOMETRA MULTICOLOR. 340. ABOUT THE NINTH PINNULE OF 

 AUSTROMETRA THETIDIS. 341. DORSAL VIEW OF GENITAL PINNULE OF AUSTROMETRA THKTIDIS. 342. 

 DISTAL PINNULES OF COMPSOMETRA SEHRATA. 343. DISTAL PINNULES OF PTILOMETRA MULLERI. 344. 

 DISTAL PINNULES OF OCEANOMETRA GIOANTEA. 345. DISTAL PINNULE OF HELIOMETRA QLACIALIS. 346. 

 DISTAL PINNULES OF LAMPROMETRA GYGES. 347. DISTAL PINNULES OF HIMEROUETRA MARTENSI. 348. 

 DISTAL PINNULES OF PROMETBA OWSTONI. 349. DISTAL PINNULES OF AMPHIMETHA DISCOIDEA. 350. 

 DISTAL PINNULES OF THALASSOMETRA VILLOSA. 



and pinnules are rarely, if ever, perfectly free from any traces of calcareous 

 structures; they may take the form of simple short spicules, which are almost 

 entirely limited to the marginal lappets, or they may be forked and branching 

 spicules or rounded cribriform plates of variable size which are movable and 



