ECTOCARPACEiE. 85 



main stems tangled. Pods immersed in the joints of the 

 branches. 



This is a very beautiful and rare species, and grows 

 in brackish water, as well as in the sea. 



Ectocarpus Mertensii. Mertens's Ectoca r pus. 



Tufts growing on mud-covered rocks and stones near 

 low-water mark, dense but not matted, from two to six 

 inches or more long. Threads branched ; branches and 

 branchlets opposite, of unequal lengths, intermixed. Pods 

 imbedded in the branchlets. 



A very pretty and well-marked species, occurring in 

 several localities, but which must, nevertheless, be con- 

 sidered rare. I have gathered it at Worthing, and I 

 have some splendid specimens which were collected at 

 Plymouth, by Mr. John Gatcombe. 



Genus XXXV. MYRIOTRICHIA. 



Fronds jointed, hair-like, limp, beset with simple, spine- 

 like branchlets, which are covered with pellucid fibres. 

 Fructification, elliptical spores without stalks, each enve- 

 loped in a transparent membrane. — Myeioteichia, from 

 the Greek murios, a thousand, and thrix, a hair. 



All the species of this genus are parasitical, and occur 

 frequently on our shores. They have neither bright 

 colours nor beautiful structure to recommend them to 

 notice; but they should, nevertheless, find their ap- 

 pointed place in every collection. 



Myriotrichia clavseformis. Club-shaped Myrio- 

 trichia. 



Fronds growing in tufts on Chorda lomentaria, about 

 half an inch long, closely beset with branchlets, which iu- 



