304 SUMMARY OF CURRENT RESEARCHES RELATING TO 



thickened or often somewhat pitted walls of the epidermal cells, in the 

 heteromorphy of the epidermal cells of the main axes, and in the pro- 

 liferating habit of many of the ultimate ramuli. E. S. G-. 



Some Marine AlgsB recently introduced into Danish Waters. 

 — L. K. EosENViNGE {Bot. Tidsskr., 1920, 37, 125-35). The four 

 species in question are Gigartina mamillosa J. Ag., TrailUeUa inlricata 

 Batters, Godium tomentosum Stackh., and G. muc7'onatuin J. Ag. 

 Gigartina mamiUosa was discovered in 1861) at Thisted in the Limf jord, 

 and was also found there in 1890 and 1893, but nowhere else in the 

 fjord. The isthmus separating the Limfjord from the North Sea was 

 broken through in 1825, before which date the salinity in that part was 

 very slight. It is now 29 p.m. The alga must have iDeen carried in by 

 a vessel on which it was growing. It is also recorded from Aarhus 

 harbour, probably introduced in the same manner. TraHJiella intricata 

 is now very common and abundant in the Western Limfjord, whither it 

 is supposed to have immigrated about 1900. It also occurs in the 

 Kattegat, but is always sterile in Danish waters. Godiwn tomentosum 

 was found in 1919 at Hirsholm, a harbonr never visited by foreign 

 vessels. Its appearance may perhaps be connected with a mine-field 

 at Herthas Flak during the war. G. nmcronatum appeared in the 

 Limfjord in the summer of 1920, undoubtedlv introduced by vessels. 



E.8. G. 



Botanical Results of the Swedish Expedition to Patag'Onia and 

 Tierra del Fuego, 1907-9. Marine Alg'ae : I. Phseophycese.— C. 

 Skottsberg {K. JSvensJc. VetenskapsaTcad. Handl., 1921, 61, No. 11, 

 56 pp., 20 figs.).' The original intention of the author was to make a 

 very detailed study of the large algal collections made on this voyage, 

 but, owing to various delays and the increased cost of publication, the 

 paper has been of necessity reduced to a list of the species with notes 

 on some of them. These notes contain information of great interest 

 and value, and clear up many doubtful points hitherto unsolved owing 

 to lack of living or sufficient material. Some of the Ectocarpacete and 

 Elachistaceaj had been handed over to Dr. Kuckuck for inclusion in his 

 proposed monograph, and after his untimely death his notes were 

 returned to Dr. Skottsberg, who embodied them in the present paper. 

 One of these notes treats of the two Falkland Islands species, Ectocarpus 

 pectinatus and Elachista (?) ramosa, which are placed in a new genus 

 Gononema. Two new species of Elachista pro\'oke a discussion on the 

 validity of species of that genus and of Myriactis. Further material of 

 Gsepidium antarcticum shows that it possesses a marked periodicity. 

 During the winter it consists of horizontal thalli, sometimes with small 

 cups, from which very short simple upright shoots arise. Later, these 

 upright shoots develop into large branched fronds like a typical Ghordaria 

 and with typical sporangia, which are here described for the first time. 

 The bladders or " colpomenia-sprosse " were found in all sizes, and 

 consist of hollow and swollen protuberances on the horizontal thallus. 

 Their development and structure are described and figured. They bear 

 gametangia in large irregular sori. The theory that the bladder-like 

 structures are " Golpomenia,''' and not an integral part of Gsepidium, is 



