PLUMULARIA. 153 



" This very rare coralline grows to the height of ten or 

 twelve inches. The root, or first beginning, consists of an 

 irregular tuft of extremely small tubes, appearing like a 

 piece of sponge to the naked eye. Several of these little 

 tubes rising together, and uniting in close contact, become 

 a stalk, which appears in the microscope curiously chan- 

 neled and indented." (Ellis.}' The stalk is generally simple. 

 In the figures by Ellis there is one in which the stalk is 

 once divided near the base. In all our specimens the stalks 

 have been simple, undivided, but composed of a number of 

 tubes, which gives it, when dry, a furrowed appearance. " In 

 each of these furrows there is a row of small holes with a 

 raised brim, as if punctures had been made by an instrument 

 pushed from within. The holes are close-set, and regular 

 in their size, form, and in the distances between them. 

 No probable conjecture of the use of these has been made." 

 (Dr. Johnston.} 



In more respects than one, our specimens of this beau- 

 tiful coralline this "palma marina," as some of the old 

 naturalists call it were singularly fine. The usual height 

 is said to be six inches, Ellis mentions ten or twelve. One 

 specimen I got in Lamlash Bay measured eighteen inches 

 from the base to the tip of the plume. One of its general 



