KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:0 5. 
f. arcta Kivrz. (KseuuM.) 
Ectocarpus arctus Kurz. Phye. gener. p. 289. 
Deser. Ectocarpus confervoides f. areta Kaguim. Skand. Ect. och Tilopt. p. 71 
fig. Corticularia arcta Kurz, Tab. Phye. 5, t. 80. 
Exsicc. Ectocarpus pseudosiliculosus Crouan, Exsice. N:o 27. 
f. siliculosa Dinuw. (KseuuM.) 
Conferva siliculosa Dituw. Conf. p. 69. 
Descr. Wctocarpus confervoides f. siliculosa KJELLM. |. c. p. 73. 
Fig. » siliculosus Lynes. Hydr. Dan. t. 43, fig. e. 
Exsice. » » Aruscu. Alg. Scand. exsicc. N:o 176. 
f. spalatina Kivrz. (Ksniim.) 
Ectocarpus spalatinus Ktrz. Phye. gener. p. 288. 
Descr. Ectocarpus confervoides f. spalatina Ksnium. |. c. p. 76. 
Fig. » spalatinus Kurz. Tab. Phyc. 5, t. 63. 
f. typica nob. 
Decsr. Kctocarpus confervoides s. s. KyEuum. |. c. p. 77. 
Fig. » patens Kurz. Tab. Phyc. 5, t. 67. 
Exsice. » litoralis var. Argscu. Alg. Scand. exsice. N:o 111. 
f. penicillata AG. 
Syst. Alg. p. 162. 
Descr. Ectocarpus confervoides f. penicillata KyeLum. |. ce. p. 80. 
Fig. Corticularia Negeliana Kurz. Tab. Phyc. 5, t. 81. 
Exsice. Ectocarpus siliculosus Argscu. Alg. Scand. exsicc. N:o 112. 
f. hiemalis Crouan (KJELLM.). 
Eetocarpus hiemalis Crovan, Alg. Finist. N:o 26; saltem ex parte. 
Descr. Ketocarpus confervoides f. hiemalis Kyerim. |. c. p. 83. 
Syn. Conferva litoralis We. Fl. Lapp. p. 513; ex parte. 
» siliculosa SomMerr. Suppl. p. 193. 
Ectocarpus confervoides KyeLuM. Spetsb. Thall. 2, p. 35; Algenv. Murm. Meer. p. 44. 
» » Keen, Nordl. Alg. p. 37. 
» Neegelianus, Gor, Algenfl. Weiss. Meer. p. 61. 
» siliculosus J. G. AG. Spetsb. Alg. Progr. p. 2; Bidr. p. 11. 
» » Croat, Fl. Dise. p. 458. 
» » Dickie, Alg. Nares, p. 7. 
Remark on the synonymy. 1 have been blamed by Gos because I have identified 
Corticularia Nageliana Koirz. with that form of Ectocarpus which ArescnouG has dis- 
tributed under the name of £. siliculosus in Alg. Scand. exsicc. N:o 112. Cp. Gost 
Algenfl. Weiss. Meer. p. 61 note 3. As far as I can judge by dried specimens, there 
is nothing to prevent such an identification. In branching and in the shape of the 
gametangia ArEscuouG’s alga resembles the plant figured by Ktrzinc so closely that 
they must be regarded as belonging to the same type. The form passes on the one 
side into H#. arctus or E. furcatus Ktrz., on the other side into EL. siliculosus Ktrz. 
