General History of the Marine Polyzoa, 145 



' Annals/ March 1885 (p. 245). 



Diachoris quadricornuta, sp. n. 



Jullien's species D. maxilla * has been referred to the 

 present form ; but in the absence of specimens of the former 

 1 should hesitate to identify them. 



Ibid. (p. 247). 



The footnote may be cancelled ; I have already given my 

 reasons for uniting Diachoris with Beania. 



* Annals,' March 1891 (p. 286). 



Flustra spinuligera^ sp. n. 



Though I have treated this form as distinct from Carhasea 

 rhizophora of Ortmann, there may, I think, be a question 

 whether it should not rather be regarded as a variety of the 

 Japanese species. There is a remarkable similarity between 

 them in most of the leading characters. 



The zooecia agree in all respects but one. In F. spimdigera 

 the margin bears a continuous line of short spines, and witliin 

 the margin and just below it there is a line of minute denticles ; 

 these are wanting in G. rhizophora. But the form of the 

 cell, the orifice, the ooecium, and the avicularium are alike in 

 both. When we come to the zoarial cliaracters we meet with 

 some dissimilarity. 



The South-African form is unilnminate and erect ; the 

 Japanese bilaminate and decumbent, and attached by tubular 

 fibres springing from the dorsal surface. 



The marginal spines, as we know, are not very constant 

 among the Polyzoa ; the internal denticles might very possibly 

 escape observation. Both unilaminate and bilaminate forms 

 occur within the limits of a species ; so that the decumbent 

 habit and the radical appendages would seem to be the most 

 important distinctive characters. Taking into account the 

 perfect agreement of the zooecia in all the most significant 

 elements, we shall, I think, best represent the relationship 

 between the two by ranking Flustra spinuUgera as a form of 

 Flustra rhizophora '\. 



* ' Cap Horn,' 74, pi. vii. fig. 3, pi. xi. fig-. 4. 



t The genus Carhasea is founded on a very trivial zoarial character, 

 and, in my judgment, should b? abolished or restricted to sucii of the 

 fonui now included in it as lu.iy represent a distinct .specitio type. 



