334 Monography of the North American CuscutinecE. 



albumen. Monotropece and Orohanchem have extremely minute 

 seeds, in some respects similar to the spores of Acotyledonous 

 plants. The seeds of Cuscutinese germinate in the ground ; but 

 soon finding the plants round which they twine, (turning con- 

 stantly to the left like all Convolvulacese,) they strike their pa- 

 pillose roots into the epidermis of the stem, from which they 

 subsequently derive their nourishment ; their own original stems 

 soon withering away, so that the plant is no longer in direct 

 communication with the earth. 



As in the Entozoa, the same species is only the same or some 

 nearly related animal, so in the Epiphyta, each species is for the 

 most part restricted to the same or similar plants. This is more 

 constantly the case in Orohanchece, where the germinating em- 

 bryo fixes itself at once upon its favorite plant ; but in Cuscuta, 

 where the seed germinates in the ground, and the stem after- 

 wards lays hold of the plant which affords its nourishment, it 

 frequently twines around all the plants in the neighborhood, and 

 is capable of extracting from them its food. Some species, how- 

 ever, are more constant in their predilections than others ; as, for 

 example, the European Cuscuta Epilinum, which never grows 

 on any other plant than flax ; and our Lepidanche Composita- 

 rum, which is confined to Solidago, Helianthus^ and some other 

 CompositcB. Yet several, like the European Cuscuta Epithy- 

 mum and the American C. Polygofiorum, live promiscuously on 

 most plants within their reach, evidently preferring, however, 

 some particular species or genus, and seldom found except in its 

 immediate vicinity. I have therefore ventured, as far as practi- 

 cable, to name the species of Cuscuta after the plant upon which 

 they grow; in accordance with the nomenclature frequently 

 adopted of late in the case of parasites, especially in the genus 

 Orobanche, (Examp. Orobanche Galii, O. Eryngii, O. iScabio- 

 see, O. SalvicB, etc.): thereby designating an important circum- 

 stance in the history of the plant. 



Before I proceed to describe the North American species known 

 to me, it may be well to present a general 



Conspectus of the species that have come under m.y observation. 



I. Cuscuta, Linn. Sepals united into a 4-5-cleft calyx. 



§ 1. Styles united into one. 



1. C. MONOGYNA, VaJd. Eastern Europe. 



§ 2. Styles two. 



