BY WILLIAM A. HASWELL, M.A., B.SC. 251 



facies of this section of the Australian marine fauna. As might 

 be expected from what is already known of the geographical 

 distribution of the Cha3thelmiuthes,*^' there is little to markedly 

 distinguish the Australian representatives of this group from 

 those of northern seas ; the species are different, but belong to 

 the same or nearly related genera. As regards the distribution 

 of the group within the Australian province itself, the only note- 

 worthy point is that the species of the tropical shores of Queens- 

 land are entirely different from those of the temperate coasts of 

 New South Wales and Victoria, a circumstance which affords 

 illustration of tliefact that Australia consists, so far as its another 

 marine zoology is concerned, of two entirely distinct provinces — 

 an intertropical or northern, and a temperate or southern, with, 

 on the whole, considering the continuity of the coast line, 

 remarkably few features in common. 



A portion of the work on which this paper is founded was 

 carried out last year during a cruise with H.M.S. " Alert " along 

 the eastern coasts of Queensland ; and I take this opportunity of 

 placing on record my grateful thanks to Captain J. F. Maclear, 

 Dr. E. W. Coppinger and the other officers of that vessel for 

 much kindness and hospitality experienced during my stay with 

 them, and for assistance liberally rendered in the way of boats 

 and men for dredging when the requirements of the survey 

 permitted. 



A. AXATOMY AND PHYSIOLOGY. 



The Elytra. 



The possession of elytra or scales is one of the most distinctive 

 points in the structure of the Aphroditacca. These elytra are 

 flattened squames of varying shape, but always more or less 

 rounded, sometimes delicate and membranaceous, at other times 

 stiff and horny, which cover the back of the annelide in a double 



* Vide Qi^atrefages, " On the Geographical Distribution of the Annelida," 

 Ann. Mag. N.H. (3) xiv., ISGl, p. 239; also Uist. Nat. dcs Auucles, t. I. 



