286 Rev. T. Hincks's Contributions towards a 



harmony with the altered views of the nature and origin of 

 species which now prevail, whilst at the same time it makes 

 identification both surer and easier. Science, in my judg- 

 ment, would be the gainer if there were more rigour in dealing 

 with meagre and insufficient descriptions of specific forms. 



Another important change in systematic method is indi- 

 cated by the increased attention which is paid to varietal 

 modifications of the type-form and also to the lesser variations 

 amongst the structural elements, in all of which " we see 

 nature still at work," preparing for the introduction of new 

 forms. 



A considerable number of new varieties of recognized 

 species are described in the present series of papers. 



In addition to the merely descriptive matter, a record of 

 the geographical range has been given as far as possible, and 

 many systematic and morphological questions have been 

 discussed. 



In an Appendix I shall correct any errors or omissions that 

 may have come to my knowledge and add a few notes on 

 special points. 



Suborder Cheilostomata. 



Family Flustridse. 



Flustea, Linnaeus. 



Flustra spinuligera, sp. n. 

 (PI. VI. figs. 1, la, lb, lc.) 



Zoarium of a light brown colour, divided into large seg- 

 ments, widening upwards and irregularly lobate *. Zooecia 

 alternate, disposed in lines, elongate, rounded at the top and 

 slightly enlarged, narrowed towards the base; margin some- 

 what thick, bearing on each side a continuous line of rather 

 short and stout spines ; area closed in by a membranous wall, 

 a little beneath the membrane, the sides of the cell traversed 

 by a line of minute and pointed denticles. Ocecium immersed, 

 rounded, surface smooth, a bar composed of two modified 

 spines across the front. Avicularia distributed over the 

 zoarium, occupying a distinct area, which ranges in a line 

 with the cells, placed obliquely, rounded at the base, the beak 

 much produced and carried up between the walls of the 

 neighbouring cells above it ; mandible broad and triangular 

 below, running out above into a slender spinous process of 

 considerable length. 



* The habit is very similar to that of F.foliacea. 



