170 



by a line, which passes obliquely proximally from the outer corner to the oppo- 

 site lateral margin almost parallel with the proximal truncated part of the poly- 

 pide-tube. The part of the basal surface of the polypide-tube, which lies distally 

 to the just mentioned angularly bent line, has an independent wall, while the 

 basal wall in the proximally directed part is exclusively or mostly formed by 

 the basal wall of the zocecium. The obliquely ascending distal wall has within 

 its basal margin a multiporous rosette-plate on each side, and a similar plate is 

 found in the distal half of each lateral wall. In the approximate centre of the 

 distal margin of the cryptocyst a larger or smaller tubercle rises, from which five 

 yellow, proximally connected bands take their origin. They appear to be fastened 

 to the covering-membrane, and the same thing seems to be the case with a 

 similar number of bands, which spring from the outer lateral wall. These bands 

 are undoubtedly parietal muscles. Each of the margins of the colony shows a 

 series of narrow kenozooecia which have a wholly membranous frontal cover 

 and no cryptocyst. 



Besides a small fragment from King George's Sound, West Australia, for which 

 my thanks are due to the late Mr. Peal, I have examined a number of colonies 

 from Australia, found in the herbarium of algse in the Botanical Museum. The 

 species has hitherto been found only on Amansia pinnatifida. 



Siphonoporella nodosa Hincks. 

 Annals Nat. Hist. ser. 5, Vol. 6, pag. 90, PI. XI, fig. 10. 

 (PI. VI, figs. 2 a, 2 b). 

 As I have only been able to examine a small fragment of this species (from 

 Australia), which I lost before I had completed my examination, I shall here 

 only make some comparative and supplenjentary observations. As in the pre- 

 ceding species we find here a proximal, but much stronger developed gymnocyst, 

 a pent-roof-shaped cryptocyst and a polypide-tube, which is continued proxi- 

 mally under the cryptocyst roof. The distal part of the polypide-tube is however 

 very short, and the whole of its basal wall is formed exclusively or mostly by 

 the basal wall of the zocecium. The distal wall is also here somewhat ascending 

 and provided with two multiporous rosette-plates. The distal half of each lateral 

 wall with 1 — 2 similar plates. 



Family Aspidostomidae. 



The zooecia, in which a raised margin is often indistinctlj' or incompletely 

 developed, are always without spines and have generally a strongly developed 

 distal end, sometimes projecting in the shape, of a pent-roof. The two opesiulse 



