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anal plate rests either on the posterior basal, or is separate from it ; but, in 
the species named, it is invariably perched on the top of the truncated apex 
of that plate. Again, in Grapliioannus, whether on the posterior basal or 
separated, from it, this anal plate extends above the plane of the radials ; but, 
in the group of species, never ; at any rate, not in the Australian. It further 
appears, from Trautschold’s description, that there may be a few small sup- 
jilemcntary plates.^ I therefore propose to restore Thialocrhms, Trautschold, 
to tlie rank of a genus, a step which had the cordial approval of my late 
friend and co-writer. Dr. P. H. Carpenter, P.P^.S., to whom I submitted casts 
and facts bearing on the generic relations of the Crinoids in question, at a 
time when much peiqolcxcd with their affinities. lie was kind enough to 
favour me with his views on the matter in writing, and his permission was 
obtained to their insertion here. 
Dr. Carpenter’s remarks on the relation of Thialocrimis to Graphio- 
crlu /(s are as follows : — 
“ In my opinion Messrs. IVachsmuth and Springer committed a great 
mistake when they redefined De Koninck’s genus Graphiocrmifs, and added a 
number of American species to it. No doubt they were right in supposing 
that Grap>hiocrinus has under-basals, concealed by the top stem-joint, but this 
bas yet to be proved in G. encrinoides. In this, however, the type, and to 
my mind the onhj species of the genus, the five basals are all equal, the 
radials form a closed ring, and the anal plate rests uj)on the upper angles 
ot two of them, separating the two costals (second, or axillary radials, 
(luctoriim). IVachsmuth and Sjiringer refer the following species to 
G raphiocrinus : — 
A. 
Scaphiocrinus carbonarius. 
,, riidis. 
,, striatus. 
,, simplex. 
,, IVachsmuthi. 
E. 
Scaphiocrinus M‘Adamsi. 
,, spinobrachiatus. 
„ tortuosus. 
Possibly the basal plates of the anal tube. 
