403 
As shown by BATTERS, I. c., the antheridia form a covering on the monosiph- 
onous branches with the exception of the two or three basal and the four to six term- 
inal cells which remain undivided. The antheridia (spermatangia) are not produced 
directly from the central cell, as asserted by BurrHam, but from a layer of small 
cells surrounding the central cell and budding the spermatangia on their outer face 
(fig. 337 B). 
As regards the development and structure of the cystocarps, reference may be made 
to the papers quoted of JanczEwskı and PhirLıps. The procarps are usually borne 
on the fourth joint from the sympodial axis (PHILLIPS), 
from the last joint of the pushed aside main axis which 
in sterile plants becomes polysiphonous (FALKENBERG). 
The spores of the gonimoblast are seriate. 
The tetrasporangia are produced in distinct stichidia 
arising in the upper part of the sympodia; their structure 
has been described by FALKENBERG (I. c. p. 649). 
The Danish specimens only reach a length of 10 cm. 
They were found growing on stony bottom in 13 to 31 
meters’ depth, attached to stones or to Delesseria sinuosa 
or Furcellaria. It was dredged in July to September. An- 
theridia and tetrasporangia were found in August, young 
cystocarps in July. 
Localities. Ns: aF, off Thyboron, 14,5 miles, 31 meters. — 
Sk: ZK’, off Lønstrup, 4 miles, 17—19 m; YL, N.W. of Hirshals, 2,5 
miles, 13 met. and deeper. — Kn: TO, Tonneberg Banke, north of 
Trindelen, 18 m; FF, Trindelen, 15 m. — Ke: ZG, Fladen, 18 m. — 
Su: Øresund, “in the deeper region of Algæ” (Lönnberg, Undersökn. 
rér. Oresunds djurlif, Uppsala 1898). 
Laurencia Lamouroux. 2 DE er 
Heterosiphonia plumosa. À, part of 
1. Laureneia pinnatifida (Gmel.) Lamouroux. male plant: EU innansyerss 
section of antheridial covering. 
625 : 1. 
Lamouroux, Essai des Thalass.. Ann. du Mus. XX, 1813 p. 130; Greville 
Alg. Brit. 1830 p. 108 tab. 14 figs. 1—5; Harvey Phye. Brit. pl. 55, 
1846; J. Agardh 1863 p. 764; Kützing Tab. phyc. XV, 1865 tab. 66; Kolkwitz, Beitr. Biol. Flor., 
Wiss. Meersunters. N. F. IV Abt. Helgoland Heft 1, 1900, p. 52; Falkenberg 1901 p. 248, Taf. 23 
figs. 20—36; Kylin 1907 p. 138; id. 1917 p. 20; id. 1923 p. 123. 
Fucus pinnatifidus Gmelin Historia Fucorum 1768, p.156 tab. 16 fig. 3; Hornemann, Flora Danica 
tab. 1478, 1813; Smith, English Botany Vol. VII pl. 1202, 1808. 
Fucus ramosissimus ete. Oeder Flor. Dan. tab. 276, 1765. 
Gelidium pinnatifidum Lyngbye Tent. 1819 p. 40 tab. 9 C. 
As regards the basal part of the frond strange discrepancies exist between the 
statements of the various authors. SmirH (Engl. Bot. 1808) and J. Acarpn describe 
it as a branched “root” (“radix fibrosa”). Turner (1808) describes it thus: Root a 
flat disk throwing out a few creeping fibres. GREVILLE (1830) and Harvey describe 
