ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 423 



Marine Algas of Casco Bay.* — F. S. Collins gives a list of marine 

 algae from Casco Bay, on the coast of Maine, U.S.A. The marine flora 

 of this region is distinctly boreal in character, corresponding more with 

 that of northern Norway and Iceland than with that of the correspond- 

 ing latitnde in Europe. This list does not profess to be complete, l)ut is 

 the result of frequent collections during many years. The number of 

 species recorded is 247, microscopic and macroscopic. 



West Indian Algae. t — F. Borgesen publishes a second instalment of 

 studies of ChlorophyceaB from the Danish West Indies, treating in the 

 present case of tlie following algJB : — Valonia (4 species), Dictyosphaeria 

 (3 species, one of which is new), Ernodesmis (a new genus created for 

 Valonia verticiUata Kiitz), Struvea (2 species, one of which is new), 

 Chainsedoris (1 species). The structure of these is described and figured. 



Phaeothamnion.l — F. L. McKeever gives an account of Phaeotham- 

 nium confer vicolum Lagerh., a brown alga which grows epiphytically on 

 algse, mosses, and aquatic Phanerogams in fresh water. It had never 

 been observed in this country till he found it in Elf Loch, on the Braid 

 Hills, near Edinburgh. He gives a resume of all that is known about 

 this alga. 



Algae of Salt Marsh. § -S. M. Baker, in her ecological account of 

 the brown seaweeds of a Xorfolk salt marsh, describes two new varieties 

 of Pelvetia, one of w'hich flourishes unattached to any stratum. She also 

 describes Fucus voluhilis Hudson, and shows tliat the species is dioicous, 

 giving photographic reproductions of the microscopic structure of the 

 conceptacles. 



Histology of the Fucacege.H— H. Le Touze publishes a contribution 

 to the histological study of the Fucacete. He distinguishes two tissues 

 — the parietal or cortical tissue, and the central tissue. His results are 

 as follows:—!. Each cell, even hyphal cells, possesses but a single 

 nucleus. There are two types of nuclei in the Fucaceai : in the uni- 

 nucleolate type the basophile substance appears condensed into a single 

 (rarely double) central mass ; in the granular type the chromatin is 

 divided into several large grains adhering mostly to the nuclear mem- 

 brane. Witli few exceptions the first type is found in the Fucese ; the 

 second in the Cystoseirese. 2. In cells near the apex, a mitoplasm and 

 an alveoplasm may be distinguished. There are no centrosomes during 

 the state of cellular repose. Death is effected by granular degenerescence. 

 3. The phffioplasts have probably a mitochondrial origin. 4. Thefucosan 

 granules are distributed throughout all the tissues of the plant. They 

 originate by a condensation of the products of the chlorophyll-assimilation 

 around special plastids. The young granules reduce osmic acid, and are 

 soluble in alcohol ; the old granules are negative in both respects ; they 

 seem definitely excreted. 5. In the parietal tissue the cellular membrane 

 is differentiated into an inner pecto-cellulose w^all and a middle lamella 



* Proc. Portland Soc. Nat. Hist., ii. (1911) pp. 257-82. 



t Bol. Tidsskr., xxxii. (1912) pp. 241-73 (figs.). 



X Trans, and Proc. Bot. Soc. Edinburgh, xxiv. (1911) pp. 176-81. 



§ -Journ. Linn. Soc. (Bot.) xl. (19] 2) pp. 275-90 (2 pis.). 



II Rev. Gen. Bot., xxiv. (1912) pp. 33-47 (1 pi. and tigs.). 



