APPENDIX. 361 



overlapping the moutli like a pent-house is also a very- 

 peculiar featui-e. 



10. C. elegans, n. sp. Tab. i. fig. 2. 



Cells elongated ovoid ; avicularia large and projecting, 

 without any superior appendage ; vittse narrow, rather 

 anterior. 



Hab. — Bass Strait, 48 fathoms. Port Dalrymple, on 

 stones at low water. 



A delicate and beautiful parasitic species ; the branches 

 slender and spreading ; colour white and very transparent. 

 Cells regular and uniform in size and shape. A very- 

 similar if not identical species occurs in Algoa Bay, South 

 Africa, the only difference between them being that the 

 latter is rather larger and has the vittse much longer ; in 

 the Australian forms these bands do not reach above the 

 middle of the cell, whilst in the South African they extend 

 as high as the mouth. 



11. C. cornuta. n. sp. 



Cells oval ; avicularia in many cells wholly transformed 

 into long pointed retrocedent spines, on one or both sides, 

 in others into shorter spines or unaltered. A'^ittse linear, 

 extremely narrow, entii'cly lateral, and extending the 

 whole length of the cell from the base of the avicularium. 



Hab. — Bass Strait, 45 fathoms. 



Colour yellowish white, growth small ; parasitic upon 

 C. amphora. As some difficulty might be experienced in 

 the discrimination of this species from C. elegans, and 

 another South African species (not the variety of C. elegans 

 above noticed), it is requisite to remark that the long retro- 

 cedent spines when present are not placed upon or super- 

 added to the a\dcularia, but tliat they seem to represent 

 an aborted or transformed state of those organs. They 

 vary much in length and size in different cells, and even 

 in those of the same branch ; as it frequently happens that 



