173 



Fucoidece. 

 C)'stoseira ericoides 

 granulata 

 foeniculacea 

 fibrosa 

 Halydrys siliquosa 

 Fucus vesiculosus 

 serratus 

 canaliculatus 

 Sporochnoideoe. 

 Desmarestia ligulata 



aculeata 

 Dichloria viridis 



Dictyotece. 

 Dictyota dichotoma 

 Dictyosiphon fceniculaceus 

 Punctaria latifolia 

 Asperococcus echinatus 



EctocarpecB. 

 Cladosteplius verticillatus 



spongiosus 

 Sphacelaria scoparia 



cirrhosa 

 Ectocarpus tomentosus 



ChordariecB. 

 Corynephora marina 



SpongiocarpecB. 

 Polyides rotundus 



Furcellariece. 

 Furcellaria fasti giata 



Floridece. 

 Delesseria sanguinea 



sinuosa 



alata 



Hypoglossum 



ruscifolia 

 Nitophyllum puuctatum, 

 [v. ocellatum 



laceratum 

 Rhodomeuia laciniata 



jubata 



palmata 

 Plocamium coccineum 

 Rhodomela subfusca 



pinastroides 

 Laurencia pinnatifida 



tenuissima 

 Cliylochladia ovalis 



kaliformis 



articulata 

 Gigartina purpurascens. 



confervoides 



acicularis 



plicata 

 Chondrus mamillosus 



crispus 



membranifolius 



Brodiaei Qius 



SphEerococcus coronopifo- 



Ptilota pluraosa 



Ceramieee. 

 Polysiphonia thuyoides 



fruticulosa 



spinulosa 



atrorubescens 



uigrescens 



fastigiata 



byssoides 

 Dasya coccinea 

 Ceramium rubrum 



diapbanum 



ciliatum 

 Grifiitbsia equisetifolia 



setacea 

 Callitbamnion Turneri 



tetricum 



ChcetophoroidecB. 

 Myrionema strangulans 



Confervece. 

 Conferva rupestris 



IcEtevirens 



pellucida 

 Siphoneee. 

 Codium tomentosum 



Ulvacece, 

 Ulva latissima 



Linza 

 Enteromorpha compressa 



Gelidium corneum 



121. True office of the Earth in relation to Plants. Although so much has been 

 written on the subject of gases evolved and absorbed by plants ; on the form and func- 

 tions of the stomata or mouths of plants ; and on the obvious numerical preponderance 

 of the stomata in the leaves and branches over those in the roots ; yet the broad asser- 

 tion that the office of the earth in relation to plants is precisely equivalent to its office 

 in relation to animals — namely, to maintain them in the position best suited to their 

 well being — has, I believe, never yet been made in print. Almost as long ago as I 

 can recollect, this phytological fact was impressed forcibly on my mind by seeing how 

 beautifully hyacinths blossom with their roots immersed in water and without a parti- 

 cle of earth that they could possibly reach. I have constantly asserted my belief on 

 this point, but have always been laughed at as a visionary and theorist. It is, how- 

 ever, with infinite satisfaction that I see my views slowly gaining ground. Each suc- 

 ceeding year diminishes the number of those who assert that plants feed on the earth 

 as we feed on meat and bread and potatoes : still, by far the larger portion of convers- 

 ing mankind religiously believe this, and most of our farmers look on a rich soil as 

 being as directly food for their wheat as a sack of barley-meal is food for their pigs. 

 Now the truth is the very converse of this : the earth feeds on plants — is increased by 

 plants — owes what is called its richness and good properties to plants. These facts 

 are not only interesting in themselves, but the ends to which they are applicable would 



