2 



Mrs 



termination was incorrect, and, in the absence of fruit, it was 

 doubtful whether the plant was a Chrysymenia and might not be 

 possibly the alga cited under the name of Lomentaria saccaia in 

 the Nereis Am. Bor. founded on Californian specimens of Du- 

 montia saccaia from Herb. Greville, and later transferred to the 

 genus Erythrocystis, by Prof J. G. Agardh. Through the kind- 

 ness of Prof. Balfour, I have been able to examine the specimens 

 of Dumontia saccaia in Herb. Greville. There are two speci- 



J» 



mens marked "California, Douglas, Hort. Soc. Lend., 1833. 

 Examination shows that both of these specimens, which are in 

 fruit, are beyond doubt Ricardia Moniagnei, Derbes. and Sol, 

 similar in all respects to the specimens of R. Moiitagnei, var. gi- 

 ganiea, from California distributed in Alg. Am. Bor. Exs. no. 58. 

 In the specimens of Douglas, as in those in Alg. Am. Bor., the 

 Ricardice were growing on Laurencia virgaia, as that species is 

 understood by American algolgists. 



The fruit of C. pseudodichoioma appears not to be common, 

 but I have received from Mrs. A. E. Bush good fruiting speci- 

 mens collected at Monterey, and the structure of the cystocarps 

 as shown in plate LXXXVHI, fig. 7, confirms the opinion previously 

 reached from an examination of the frond that the plant is a 

 Chrysymenia. The figure, it should be said, was drawn from a 

 section of a plant which had been pressed, and therefore the two 

 sides of the sack are brought much closer together than they are 

 in the living plant. The wall of the cystocarp is formed from 

 the enlarged walls of the sack, and the spores are arranged 

 around the carpogenic cell in a somewhat reniform mass com- 

 posed of different lobules in which the spores are densely packed 

 together, but arranged in short digitate moniliform rows, as can 

 be seen by applying reagents. In fig. 8 the method of branch- 

 ing is shown. At the base of fli^ lo^^^o*- .„„i. ...i,.- 1. . • „.„. 



the mam stipe a branch is given off at right angles which also ends 

 m a sack and the process is again repeated. At the point a, 

 where another branch is given off, there is an indentation on the 

 upper side of the angle formed with the main stipe which marks 

 the spot where there had previously been a terminal sack which 

 has now disappeared, so that the large sack of the figure which 



