480 



Dansk Botanisk Arkiv, Bd. 3. Nr. 1. 



having shorter processes with broad bases and acute or more 

 roundish apices everywhere, except at the side facing the host 

 plant. As soon as I observed them I supposed that I had to do 

 with a parasitic Floridean and after having found, not only plants 

 with neutral spores, but also antheridial and female plants, this 

 seemed quite clear and was also amply proved by closer examination. 



The parasite occurs in all parts of the 

 host plant, upon young thin filaments as well 

 as upon thicker main filaments; I have 

 especially found many of them upon the 

 tendrils of the Hypnea. The specimens attain 

 the size of a pinhead, their diameter having 

 a length of up to ^/^ mm. 



As the material has been preserved in 

 alcohol I am unable to tell anything about 

 the colour of the plant. 



From a transverse section (Fig, 434, 

 a, b, c) through the host and parasite is 

 seen that their growing together is very inti- 

 mate, the parasite having a very hyper- 

 plastic effect upon the tissue of the host. 

 Thus the epidermal layer of the Hypnea is 

 quite disorganized, its cells becoming in such 

 a way transformed and intermingled among 

 the cells of the parasite that it is generally 

 quite impossible to say, where the one ends 

 and the other begins. The parasite does not penetrate to any 

 great extent into the tissue of the host. I have never found any 

 of its filaments between the large cells in the medullary tissue of 

 the Hypnea. 



The figure 434 b shows a part of a transverse section of Hyp- 

 nea, and the parasite. We see some of the large cells belonging 

 to the central body of the Hypnea, but the very regular corti- 

 cal layer of this plant is much damaged; perhaps two or three 

 of the largest roundish cells are from this tissue, but this cannot 

 be stated with certainty. And after having stained the transverse 

 section in Hoffmann's violet, dissolved in glycerine and water it 

 is easily seen that the cells of the parasite and those of the 

 Hypnea are connected by pores quite in the same manner as de- 



Fig. 433. Hypneocolax 



stellaris nov. spec. Two 



plants fixed to the host 



plant. (About 8:1.) 



