four ntw Species of Fucus. 1 29 



much li^is been already written upon that fubjed, the Society will 

 perhaps excufe me if I trel'pafs Ibmewhat upon their time hy a 

 flit^ht digreffion refpefting it. The fruit of Fucus Hypogkjfum, as 

 is well known, is fometimes found in fmall globular caplulcs fituatcd 

 upon the midrib of the leaves, while in other fpecimens no traces of 

 thefe capfulcs are apparent, but minute dark, feeds are difcovered in 

 two fmall rows on each fide of the midrib, and parallel to it : a cir- 

 cumflance which with fome botanifts has given rife to the conjec- 

 ture that this Fucus may poflTibly be dioicous, while others have 

 carried the matter fo far as to wifh to conftitute two diftin6l fpecies. 

 The latter idea however is done away by plants being occafionally 

 found in which both kinds of fruftification, as they are called, may 

 be difcovered upon the fame plant ; and the former fuppofition has 

 always appeared to mc equally ill-founded, from my once having ex- 

 amined a plant in which the capfule was aiSlually burfling, and the 

 feeds partly difcharged. I have no hefitation in owning, that I 

 never could account for thefe feeds, fuppofing them to be cafually 

 fcattered, adhering in fuch regular lines as is always the cafe ; nor 

 can I fee any rcafon for that part of the membrane upon which 

 they are difpofed being of a darker colour, and apparently thicker 

 fubftance, than the reft of the leaf : thefe are difficulties which I hope 

 other botanifts will remove, but which do not appear to me of 

 fufficient importance to induce me to accede to the idea of Fuci 

 being raonoicous or dioicous. I am indeed on the contrary per- 

 fuaded that they prove nothing, as many other Fuci, among which 

 are to be enumerated the following, have their feeds equally con- 

 tained in capfules, and afterwards difperfed upon the frond, though 

 without the fame appearance of regularity: thefe are Fucus alatus^ 

 ovalis, dafyphyllus, nrticulatus, kaliformis, clavellofus, teiiu'tjjimus, 

 and pinmtljiaus. From a confideration of thefe and other circum- 

 ftances, I have been led to conjefture, that in the above-mentioned 

 Vol. VI. S Fuci 



