506 ON A COLLECTION OF ECHINODERMATA FROM AUSTRALIA, 



A somewhat similar statement with regard to Dr. Gray has 

 been made by Mr. Alex. Agassiz, and with this I dealt in the 

 early part of last year,* when T took occasion to point out the 

 inconstancy and unimportance of the characters which were 

 regarded as distinguishing Peronella from Laganum. 



Breynia australasice. — When the specimens of this species 

 attain a great size their general appearance is not a little altered, 

 owing to the want of proportionate increase in the long abactinal 

 spines, which, no doubt, are more needed by younger than by 

 older and stouter individuals. 



Hemiaster apicatus. — The specimens in which Mr. Tenison- 

 Woods formed his new species of Hemiaster were without spines ; 

 the single specimen now before me is, I fancy, a representative of 

 that species ; as it is well provided with spines I stand aside to 

 allow Mr. Woods to complete its description. 



Class. Holothuroidea. 



Unfortunately many of the species of this group are represented 

 by single individuals only, and as the whole of the Holothurian 

 collection in the British Museum has not as yet been specifically 

 determined, the list is unsatisfactory and incomplete. 



1. Colochirus tuberculosus. 

 Port Denison. 



2 Colochirus australis. 

 Port Jackson. 



3. Actinocucumis dijfficilis. 



[No locality : the Alert collected it in Torres Straits] 



4. Thyone buccalis. Vide infra. 



Port Denison. 



5 Orcula persjricillum. 



Port Denison, Port Stephens. 



*Ann. N. H. (5) XI., p. 130, etc. 



