154 Co/. Vei.ley'j Remarh on the Nature 



taken to preferve a drift conneftion, and uniform correfpondence, 

 between the parts defcribed, and the definitions by which the theory 

 is fnpported. Gicrtner, in his remarks upon fome of the Fuci, find- 

 ing that their fecundation was efFefted by an internal procefs, main- 

 tains like wife, that the pai t contaming the feeds is alfo endued with 

 the faculty of impregnation. But ihis author gives an unphilofo- 

 phical and a fanciful caft to his hypothefis, in adopting an unifexual 

 difl:in£tion,when he fuppofes that the female organ impregnates it- 



felf, or rather, the ovula which it contains " quod ipfe uterus 



fua foecundet ovula, et quod ille ipfe officia genitalium utriufque 



fex^s, prasftet folus." Upon examining the mucilaginous vefi- 



cles (or, ftriftly fpeaking, the diftended fummits) in which the feeds 

 are placed, and confidered alfo by Mr. Correa de Serra as the anthe- 

 rs, it will appear that the feeds are very feldom fixed in a loofe 

 and naked ftate, but contained in minute hard coriaceous tubercles, 

 on all fides impervious*, and moft firmly attached to the interior 

 furfacc of the fummit, in the veficular Fuci\ and that in thefe 

 tenacious tubercles the feeds may frequently be difcovered long 

 before the folid cellular rhafs becomes changed into a mucilaginous 

 fubftance. Again, in feveral fpecies, the central fubftance, in which 

 the feeds or pericarps are placed, always remains in an invariably 

 folid ftate, and is never converted into mucilage. This is decidedly 

 the cafe in the Fucus ferratus -^ , and I never found it otherwife in the 

 Fucus nodojus and fome others: and yet the feeds of both thofe plants 

 are produced in the fame manner as in the Fucus veficulo/us. From 

 thefe fafts there is great reafon to conclude, that the mucus, which 

 is found at certain feafons in feveral of the Fuci, is not eflentially 

 ncceffary to their impregnation. And as it feems to abound moft in 



* See the horizontal fetlion of one of the fummits of Fucus veficulofus, in which the 

 tubercles or pericarps are reprefented. Veil. Marine Plants-, plate i. 



t See an horizontal feftion of this Fucus magnified, Marinf Plants, fhte i. 



the 



