has been long well known to botanifts, and the fi.igulavity of its flruclure pre- 

 cludes the poflibiiity of its ever having been confounded with any other. The 

 whole plant forms an oblong net-like tube, varying from a few inches to a foot 

 in length, and from half an inch to two inches in diameter ; being all formed of 

 rnefhes which arc moft ufually pentagonal, but fome are compofed of four and 

 forr.e of fix fides. Each fide is formed by a fingle joint which branches in a 

 dichotomous and almoft divaricated manner at each end, fo that thefe branches 

 a (lift in forming other mefhes. The joints are cylindrical, and vary greatly in 

 the fame plant, fome being twice as large as others, and the breadth varies 

 proportionably from the fize of human to that of the thicker! horfe hair. 

 Reipetting the propagation of this fpecies I cannot do better than copy the 

 result of M. Vaucher's observations ; they are fo extremely curious and 

 interefting that I earn.-ftiy recommend them to the notice of fuch botauifts as 

 refide in the neighourhood in which the plant grows, and (hail only add that I 

 long hefitated to give them credit, but confefs that the few obfervations which 

 my opportunities have allowed me to make tend ftrongly to confirm them. 



" Enfin, lc 24. Germinal j'arrivai a ce but tant define, et je vis d'un feul coup 

 d'ceil, tcute la reproduction de FhydrodiGye. Chacun des cinq filets qui 

 torment le pentagone commenca a se renfler legerement, fur tout a fes extrr- 

 mites. Enfuite il s'en fepara, non pas par une rupture proprement dite, mais 

 en fortant de l'interieur de la membrane dans laquelle il etait contenu, et qui 

 fans doute s'etait ouverte ; et apres cette fcparalion, il flotta dans 1'eau fous la 

 forme d'un baton cylindrique. Bicntot il s'aplatit, et eprouva un alteration que 

 je comparerai a celle qu'un commencement de fufion produit fur les metaux ; 

 ensuite il s'agrandit infenfiblement dans tous les fens, et les mailles dont la 

 reunion le conftituait s'etant ecartees les unes des autres, il devint lui meme un 

 nouveau refeau que Ton diftinguait au microfcope. Bientot ces mailles purent 

 etre obfervi.es a la vue fimple, et enfin chaque baton fut totalement change en 

 un refeau enticrement femblable a celui clout il faifait partie. Toutes ces tranf- 

 formations s'operercnt dans l'cfpace de quelques jours, et au bout de deux ou 

 Irois mois les jeunes refeaux avaient acquis toutes les dimenfions dont ils 



