of South Devon and South Cornwall. 253 



thorns off the Deadman. One specimen in my possession is 

 more than 4 inches high, and measures not less than 6 inches 

 across. The main stem is of great thickness, and the whole 

 bears a striking resemblance to an aged tree. 



The S. Gayi of Lamouroux is the S. polyzonias, var. /3, of 

 Johnston ("caulescent, pinnate"). Its very distinct habit, 

 compound stem, and pinnate branching seem to entitle it to 

 specific rank. 



3. S. tenella, Alder, Northumb. & Durham Cat. pi. 2. figs. 3-6. 



Between tide-mai'ks; probably not uncommon. 

 [Filey, Yorkshire.] 



4. S. fusiformis, n. sp. Plate VI. figs. 7, 8. 



Minute; stem slender, slightly zigzag, generally unbranched, 

 annulated at the base and below each cell ; cells alternate, 

 bent in opposite directions, elongate, somewhat flask-shaped, 

 smooth, — aperture quadridentate, with an operculum com- 

 posed of four pieces; each cell and its internode of a fusiform 

 figure. Gonothecfle elongate, slender, tapering above and 

 below, ribbed across, produced at the upper extremity into a 

 short neck and toothed, springing here and there just below 

 a cell. Height about a quarter of an inch. 



Between tide-marks. 



This species presents the appearance of a single series of fusi- 

 form pieces, springing one from the side of the other about 

 midway, and bending alternately in opposite directions. Its 

 nearest ally is the S. tenella of Alder, from which it differs in 

 the shape of the cells and capsules. 



It was first detected by Mr. Alder, who noticed it amongst 

 some Devon zoophytes which I had sent him for examination. 



5. S. rugosa, Linn. 



Generally on Flustra foliacea; not so common as in the 

 North. 



6. S. pumila, Linn. 



Universally distributed, on weed and rock between tide-marks. 



7. S. gracilis, Hassall. 



Torbay, between tide-marks. 



Nearly allied to the preceding, from which, however, it differs 

 in the minute characters. It is also of much slenderer habit. 



8. S. rosacea, Linn. 

 Very common ; parasitical on other zoophytes. 



