G. CYMODOCEA. 95 



matter, with which the numerous Polypi placed on the 

 surface of the stem are connected : this circumstance 

 retains it in the second order ; it is in reality an inter- 

 mediate between the two. 



The Cymodoceas are either simple or slightly 

 branching. 



Their substance horny, rather transparent, and fra- 

 gile. 



Their size varies as well as their colour, which is 

 sometimes a reddish fawn, at other times lighter and 

 more bright. 



They adhere to solid bodies by a fine fibrous and 

 extended base, from which issue the stems, or rather, 

 on which the stems spread and twist before they rise. 



One species has been brought from the Antil- 

 les, and another from the English coast, which two 

 constitute all of the genus as yet known : the spe- 

 cies will probably prove more numerous, when more 

 frequently collected and attentively observed. 



SIMPLE. 



1. Cymodocea simplex. Base branching; stem 

 simple, and slightly undulated ; cells alternate, long, 

 and filiform ; colour, a yellow fawn ; height, ten or 

 twelve centimetres. — Plate 7. fig. 2. a. A. 



England and Ireland. 



BRANCHING. 



2. Cymodocea rarnosa. Stem a little branching ; 

 cells opposite at each ring ; colour, a brown fawn ; 

 height, three or four centimetres. — Plate 7. fig. 1. a. A. 



Antilles. 



