48 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



Australia for the Australian Museum, but had not been able to examine any Western 

 AustraUan material excepting the two or three specimens recorded m the Gazelle 

 report, and so this offer was more than usually attractive. 



The report upon Doctor Michaelsen's collection begins with a detailed history 

 of the work done in the region, with a bibliography, followed by a detailed discussion 

 of the faunal relationships of the Australian coasts and an annotated list of the 

 species represented. These are the follo\nng: 



Comatulella brachiolata. Comanthus (Vania) annulata. 



Comatula purpurea. Zygometra microdiscus. 



Comaster typica. Zygometra elegans.^ 



Comantheria briareus. Amphimetra discoidea. 



Comanthina belli. Dichrometra tenera. 



Comanthus (Bennettia) trichoptera. Ptilometra macronema. 



Compsometra incommoda. 



The generic name Comatulella is new, but it appears merel}' in combination with 

 (Comatula) brachiolata of Lamarck. 



Comatulella brachiolata, previously known only from Lamarck's original descrip- 

 tion and Miiller's description of Alecto rosea, is discussed in great detail on the basis 

 of a specimen from Port Phillip in the British Museum and others in the present 

 collection from Koombana Bay and (?) vicinity of Perth. 



It is pointed out that many species inhabiting relatively cold water differ from 

 the comparable species inhabiting warmer water in having short and stout arms 

 and short-segmented cirri. While cold appears to delay the metabolic processes 

 so that the formation of the skeleton outstrips the growth of all the other structures, 

 causing the arms to become short and stout, warmth seems to attain the same end 

 by inducing a very rapid and early development of the sexual products which hinders 

 the development of all the other structures, though it has no effect upon the skeleton 

 formation. Whereas arm shortening by cold progresses equally on all the arms, 

 arm shortening by warmth-induced sexual maturity affects, in the Comasteridae, 

 the posterior arms first and is very often entirely confined to them. This is said 

 to be due to their relative remoteness from the ring systems about the excentric 

 mouth. Attention is called to the "pseudo-biserialism" in the arms of Comatulella 

 brachiolata. 



A specimen of Dichrometra tenera with 7 rays and 57 arms is recorded. 



Young specimens of Ptilometra macronema are described. Antedon wilsoni of 

 Bell and Himerometra paedophora of H. L. Clark are the young respectivelj^ of 

 Pt. macronema and Pt. millleri. 



The memoir ends with a list showing the association of species and a list of the 

 unidentified crinoids reported from Western Australia. 



The genus Ptilometra is placed under the family Thalassometridae instead of 

 under the family Tropiometridae as previously. 



The monograph on the recent crinoids of Australia, based on the collections of 

 the Austrahan Museum at Sydney, appeared on August 17. In the introduction the 

 importance of the study of the recent crinoids is emphasized and the present status 



