may he terminal on the long hranches. From the first the cells hear usually only 

 one sporangium or a sporangium-hearing hranchlet, hut later further sporangia may 

 develop so that a great number of the cells bear two or three sporangia. When 

 two sporangia occur, they may he opposite or near to each other, hut a spor- 

 angium may also he placed under another sporangium or under a branch (fig. C). 

 The cells giving off a branch bear frequently a sporangium opposite to it. Mono- 

 sporangia were not observed. 



Identical specimens were found in two localities on the north coast of Sealand, 

 growing in Diimontia filiformis in the month of May. It cannot be confused with 

 any other known species. As to its relation to Ch. cytophaga see this species. 



Localities. Ke: Harbour of Gilleleje, inner side of the mole. — Su: Harbour of Helsingar. 



18. Chaiitransia Nemaliouis (De Not.) Ard. et Straf. 



Akimssone e Stuai fokello, Enum. delle Alghe di Liguria, Milano 1877 p. 167. 



CaUithamnion Nemalionis Di; Notakis, Erbar. Crittogam. Italiano, no. 952 (c. descript.) ; Aiidissone, Pro- 



spetto delle Ceramiee italiche, 1867 p. 17, Tav. I fig. 1 — 3. 

 Acrochcetium Nemalionis Bohnet (1904) p. XX. 



Chantransia Saviana (Menegli.) Audissone, Phycol. Mediterr. 1883 p. 276 ex parte. 



As shown by Bornet, the CaUithamnion Nemalionis described by De Notaris 

 has a system of filaments endophytic in the frond of Nemalion lubricum, on which 

 it forms numerous 4 — 5 mm. high tufts. The same mode of growth was observed 

 in a Chaniransia growing in Nemalion mnltifidum at Struer in the Limfjord. As it 

 fully agreed with the description of De Notaris and with his above-quoted original 

 specimens, which I have been enabled to examine through the great kindness of 

 Dr. Bornet, I refer it to the same species without any doubt. Ardissone has later 

 confused this species with one or perhaps more others under the name of Chan- 

 transia Saviana (Menegh.) Ard.; as however Meneghini's description refers to a species 

 growing on Zostera leaves and certainly different from De Notaris' species, it is 

 unwarranted to replace the name of the latter with that of Meneghini. 



The plant has long ramilied filaments growing widely in the interior of the 

 host and here and there sending out through the surface of the host free filaments 

 giving rise to new tufts; the number of tufts occurring on the same frond of Ne- 

 malion may therefore be very great. The walls of the endophytic filaments are 

 often a little sinuous on account of their growth between the cells of the host; 

 the cells are usually 8 to 11/^ thick, 3,5 to 5 diameters long. They contain in the 

 middle a narrow belt-shaped chromatophore with a parietal pyienoid. When the 

 endophytic filaments rise from the basal part of the erect filaments they are given 

 ofT from the lower end of the cells while the upright branches are given off at 

 their upper end, and a similar polarity is as a rule, though not always, present in 

 the endophytic filaments (fig. 54 A). 



The erect filaments greatly resemble those of Ch. corymbifera and Ch. Thuretii; 

 they form up to 5 mm. high tufts with spread branches which are multilateral but 



