Development of Cassytha filiformis, L. 415 



The large amount of mucilage produced is probably pro- 

 tective in character, as in the Cactaceae and other xero- 

 phytes. Cactaceous plants and Cassytha not unfrequently 

 grow side by side. 



The plant is not omnivorous in its parasitism, though 

 the luxuriant appearance in its native haunts would lead one 

 at first to suppose this. The seedlings raised in our green- 

 houses refused to attach to several hosts that were offered 

 them, and seemed to prefer leguminous plants, though the 

 long list of hosts observed shows that in the wild state it by 

 no means confines its attention to this order. 



Cassytha HUformis is thus a unique member of the Laura- 

 ceae and departs widely from its order in many structural 

 details. 



The writer hopes, in a later paper, to deal with the floral 

 structure, which presents interesting peculiarities, particu- 

 larly in its sporangial organs. 



EXPLANATION OF PLATES. 



Fig. I. Longitudinal section of mature fruit. 



Fig. 2. Portion of same, enlarged, somewhat diagrammatic. Reference 

 figures apply to Figs, i and 2 alike. 

 1-4 Receptacle. 



5 Epicarp. 



6 and 7 Mesocarp. 



8 Horny layer. 



9 Indusium. 



10 Tegmen. 



11 Raphe. 



12 Cotyledon. 



13 Radicle. 



Fig. 3. Cross section of embryo showing two cotyledons and connec- 

 tion of one by incipient bundle strands with hypocotyl. 



Fig. 4. Young seedlings of Cassytha. 



Figs. 5, 6, 7. Stages in the distribution of xylem and phloem strands 

 into the four side rootlets. 



5. Condition in the hypocotyl. 



6. In the root, above branches. 



