100 



HALF AN HOUR WITH CORALLINES. 



Fig. 53. 



It is more slender and delicate than the majority 

 of the pinnate zoophytes, and is cast ashore 

 in large tangled masses. It may easily be known 

 by its zig-zag stems, and its peculiar colour and 

 delicacy. As may be seen in the illustration, the 

 calycles are flask-shaped, and the capsules pear- 

 shaped, with a short tubular mouth. Sertularia fusca 



is rather a rare species, 

 and is very small, with 

 its calycles in two rows, 

 and the mouths of the 

 calycles turned in oppo- 

 site directions. The 

 "Squirrel's Tail Coral- 

 line " (Sertularia ar- 

 grentea, Pig. 53) is also 

 small, but its branches 

 are very rigid and erect. 

 The calycles are short, 

 and swollen below. It 

 is the most common of 

 all the species which 

 occur on shells in deep 

 water, and, after a storm, 

 when the empty valves are cast on the beach, it may 

 be found dead, but still adhering to them. The " Sea- 

 cypress Coralline " (Sertularia cupressina, Pig. 54) has 

 long wiry stems, with its branches drooping, and not 

 as rigid as in the last mentioned species. Its calycles 

 are longer, tubular, and with a two-lipped aperture, 



Sertularia argentea. a. calycles ; 

 6. capsule. 



