274 Dr. Greville on some new species of Sargassum. 



joints with which it is provided, render it extremely probable that 

 the trumpet-shaped processes are the dilated footstalks upon 

 which the cells themselves are ultimately to be developed. 



The position of the several joints is not always exactly the 

 same ; one however is usually found at the commencement of the 

 long footstalk, another near its termination and at^ the base of 

 the trumpet-shaped process, a third between the cell and this 

 process, and a fourth midway on the cell itself, which sometimes 

 exhibits a constriction in the situation of the joint or line of 

 division. 



Occasionally also the spines, which would appear to be them- 

 selves trumpet-shaped processes in progress of development, are 

 jointed. 



The several branches forming the skeleton of the polypidom 

 generally spring from the important trumpet-shaped processes, 

 but occasionally also from the back of the polype-cells themselves. 



This zoophyte is best examined with object-glasses of 1 and \ 

 an inch foci, and will well repay a careful examination. 



22 Old Square, Lincoln's Inn, July 19th, 1848. 



XXX. — Algce Orientates : — Descriptions of new Species belonging 

 to the genus Sargassum. By R. K. Greville, LL.D. &c* 



[Continued from p. 206.] 



[With a Plate.] 



Many of the species which I now propose to describe from time 

 to time were communicated to me some years ago by my excel- 

 lent friend Dr. Robert Wight, Surgeon on the Madras Establish- 

 ment ; a gentleman well-known by his valuable f Illustrations of 

 Indian Botany/ and for his untiring investigations into the ve- 

 getable productions of our Indian possessions. These Algae were 

 to have been published in the f Prodromus Flora? Peninsula? 

 India? Orientalis/ a work undertaken by him in conjunction with 

 Dr. Walker-Arnott, and calculated to add largely to the well- 

 founded reputation of both parties. The second volume, however, 

 having been unfortunately suspended, I have been induced in the 

 mean time to give them to the botanical world in the present 

 form, through the medium of the Botanical Society. 



WlGHTIANJE. 



4. Sargassum echinocarpum (nob.) ; caule cylindraceo, ramosissimo ; 

 foliis oblongo-lanceolatis, dentatis, uninerviis ; vesiculis plus 

 minusve ovalibus, petiolatis, petiolis latioribus, foliaceis ; recep- 



* Read before the Botanical Society of Edinburgh. 



