V. CORALLINACE.E. 85 



recurved, squarrose ; articulations cylindrical, four to six times as long as 

 broad. 



Hab. Bahia Honda, Pro/. Tuomey. (70). (v. s. in Herb. T. C. D.) 



I cannot satisfactorily refer the specimen received from Prof. Tuomey to any 

 described species. It most resembles /. rubens in written character, but is much 

 smaller and more slender, having more the aspect of J. antennina, Kiitz. from which 

 its much longer articulations separate it. 



in. AMPHIROA. Lamoiir. 



Frond terete, compressed, or flat, calcareous, articulated, dichotomous or pinnated. 

 Nodes cartilaginous, more or less evident, sometimes elongate, naked or covered with 

 tubercles. Conceptacles conical, wartlike, sessile on the disc of one of the articu- 

 lations, furnished with an apical pore, and containing in the base of the cavity, a 

 tuft of erect pyriform, at length four-parted spore-threads. 



An extensive genus, chiefly found in the Southern and Pacific Oceans, where 

 many of the larger and more beautiful species abound. A few occur in the 

 Mediterranean, and in the Tropical Atlantic. There is much variety of habit 

 among them, and Decaisne has divided the genus into four subgenera, two only of 

 which are represented in the North Amei'ican Flora. The species of the first sub- 

 genus have a habit quite peculiar, and are much more brittle than any other of the 

 jointed Corallines. Those of the second group have the habit of Corallina, from 

 which they are only to be known by the fructification. 



SuB-GENXJS 1. Euampldroa. Articidations linear, elongate, terete or subcompressed. 

 Conceptacles scattered, numerous. 



1. Amphiroa fragilissima, Lamour. ; frond dichotomous, lobust, attenuated 

 upwards, very fragile ; the axils wide, and branches spreading ; articulations cylin- 

 drical, smooth, four or five times as long as broad. Lamour. Cor. p. 298. Kiitz. 

 Sp. Alg. p. 700. Ellis and Soland. Cor. t. 21, Jig. d. (not characteristic). 



Hab. Florida Keys. Key Wesl, W. H. H. (v. v.) 



Fronds 2 — 3 inches high, very fragile, as tliick as sparrow's quill below, gradually 



