38 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



On June 19 descriptions of 17 new species of crinoids were published; five of 

 these were from the Albatross West Indian collections, and the remaining twelve 

 were from the collections of the Investigator in the Indian Ocean. These new species 

 were: 



Eudiocrinus ornatus. Crinometra pulchra. 



Amphimetra mortenseni. Crinometra margaritacea. 



Heterometra compta. Crinometra concinna. 



Heterometra singularis. Crinometra insculpta. 



Stepfianometra coronata. Crinometra gemmata. 



Colobometra discolor. Psathyrometra mira. 



Cyllometra taprobanes. Mastigometra micropoda. 



Crotalometra annandalei. Hypalocrinus springeri. 



Hypalocrinus ornattLS. 



On the same date four new species of Rhizocrinus were described, the history of 

 the genus was traced in detail, and the included species were tentatively segregated 

 in three groups. The new species were : 



Rhizocrinus conijer. Rhizocrinus sabae. 



Rhizocrinus brevis. Rhizocrinus robustus. 



The three groups were characterized as follows : 



1. Basals anchylosed, without sutui'es {R. lojotensis; R. verrilU). 



2. Basals always separated by distinct sutures; stem comparatively slender, the 

 longer colunmals being at least twice as long as broad; calyx distinctly conical {R. 

 conifer; R. brevis; R. robustus; R. chuni). 



3. Basals always separated by distinct sutures; stem very stout, the longer 

 columnals being but little longer than broad; calyx approaching the cylindrical {R. 

 rawsonii; R. parjaiti; R. weberi; R. sabae). 



On June 25 the third instalment of new forms from the Indian Ocean was pub- 

 lished. These were: 



Comatula micraster. Crotalometra sentijera. 



Comaster parvus. Thalassometra attenuata. 



Mariametra margariti/era. Pachylometra invenusta. 



Cenometra herdmani. Psathyrometra gracillima. 



Cenometra insueta. Trichometra obscura. 



Cyllometra soluta. Hypalocrinus liliaceus. 



Asterometra mirijica. Bathycrinus woodmasoni. 



Asterometra acerba. Bathycrinus paradoxus. 



A new genus, Mariametra (genotype Himerometra subcarinata A. H. Clark, 1908) 

 is diagnosed, and attention is called to the similarity of Bathycrinus paradoxus and 

 Perrier's Ilyocrinus recuperatus, and to the similarity of both to Crema's Apiocrinus 

 recubariensis. 



On August 23 five more comatuhds were described, which were: 

 Comanthus (Comanthus) pinguis. Craspedometra aliena. 



Comanthus {Comanthus) samoana. Amphimetra parilis. 



Ptilometra splendida. 



