218 F. A. BEDWELL ON A METHOD OF EXAMINING 



the length of the piece extracted, for owing to their shape only a 

 small portion of them can be drawn out in this way. They can 

 always be found by looking at the base, or by counting from the 

 primary septa a\ a 2 in Fig. 5, and these last can usually be traced 

 in the epidermis by the extra thickness of their lines of junction. 

 The same plan answers with T. crassicomis, only the epidermis must 

 be first scraped off the part to be examined. 



Part II. 



The above observations led me to one or two very interesting 

 conclusions. 



Before I was at all acquainted with the true anatomy of the 

 animal, I was struck with the presence in each of them upon dis- 

 section of a remarkable and beautifully plicated or fluted organ, 

 quite distinct from the craspedum, though like it in size, and entangled 

 with it. A specimen taken from A. mesembryunthemumvf&s seen to be 

 a lovely green, transversely ribbed or fluted with absolute regularity, 

 ciliated and spotted in two regular lines, with white spots of extreme 

 minuteness. In each different species of the Actinidce I found 

 the organ of a different colour, but in all it preserved the 

 characteristics above described, namely, the flutings and the white 

 spots. It was not, however, until I had discovered the above 

 mentioned method of dealing with A. mesembryanthemum that I was 

 able to make out its true attitude as a distinct organ in that animal, 

 and in other varieties. These I will now describe. 



In A. mesembryanthemum the craspedum grows solely on a projec- 

 tion from the primary secondary and tertiary septa — very rarely, if 

 ever, on the quaternaries. This projection is shown in Fig. 6. pi. XII, 

 where the craspedum and its band has been cut off to show the eggs, 

 which in A. mesembryanthemum also lie on this same projection and 

 on each side of it, and nowhere else in that Actinia. These eggs are 

 of arose colour, or sometimes a light orange, and the projections on 

 which they appear are seen directly the base is opened, as above 

 directed. Now from this projection upwards towards the disc the 

 edge of the septum in A. mesembryanthemum is edged with the fluted 

 organ. Fig. 2, pi. XI, shows the organ as seen under the microscope, 

 attached in places to the septum, and detached from it in others — 

 the septum having contracted down to a false attitude, after being 



