404 



sporangium, while others bear botb terminal and lateral. The 



sporangia are about 18 fi thick and 50 (i long. 



This species belongs to the sublittoral zone and is a fairly 



common epiphyte on several larger algæ. It has been found in 

 the open sea as well as in sheltered localities 

 and bears both plurilocular and unilocular 

 sporangia. The plurilocular sporangia occurred 

 in May, June, July, November and December, 

 the unilocular in April, May and November. 



F. typica has been found in the following 

 piaces: —Vid.: Ostvig ^H.J.); Ost.: Glibre (!); Str.: 

 Thorshavn (H. J., !), Gliversnæs (!); San do: Trold- 

 hoved (!); Syd.: Trangisvaag (Ostenfeld), Frodebo (!), 

 Vaags Ejde (!), Vaagsfjord (H. J.). F. pygmæa: — 

 Kun 6 (H. J.); Syd.: Vaags Ejde (!). 



85. E. siliculosus (Dilhv.) Lyngb., Hydro- 

 phyt., p. 131, tab. 43 C; Kuckuck, Beitråge zur 

 Kenntnis einiger Ectocarpus- Arten der Kieler 

 Fohrde, p. 15. 



f. typica Kuckuck, 1. c. 



f. arcta (Kutz.) Kuckuck, 1. c. 



f. varians Kuckuck, Ectocarpus siliculosus 

 Dilhv. sp. forina varians, ein Beispil fur ausser- 

 ordentliche Schwankungen der pluriloculåren 

 Sporangienform (Berichte deutsch. bot. Gesellsch., 

 Band X, 1892, p. 256, taf. XIII). 



Ectocarpus siliculosus is a very variable 

 species, and its outward appearance dillers 

 considerably, hence it is often difficult to dis- 

 tinguish from the nearest allied Ectocarpus- 

 species. 



The specimens referred to f. typica usually 

 agree fairly well with Kuckuck's figs. 1 — 2, 

 1. c, though as a rule it is comparatively rare for their sporangia 

 to terminate simply in a long, colourless hair, they being most 

 commonly only drawn out into a longer point. The main filaments 

 vary from 40 // to 70 // in thickness. 



The specimens referred to f. arcta are particularly eharacterized 

 by their shorter sporangia, and in this they resemble Ectocarpus 

 confervoides from whicb they differ, however, amongst other things 





Fig. 66. Ectocarpus confervoi- 

 des (Roth) f. pygmæa Aresch. 

 Part of a plant with terminal 

 sporangium, and portion of a 

 filament with lateral sporan- 

 gia. 80: 1 and 150 : 1. 



