282 ECOLOGY [Bot. Absts. 



undoubted mitochondria are abundant in the embryonic region, plastids are abundant farther 

 back, and between the two are bodies apparently intermediate in character. Evidence is 

 presented that at least some of the "oil bodies" or "elaioplasts" of Preissia are true plastids. 

 Mitochondria are also present in this genus in the growing region of the disc, and are appar- 

 ently related to certain of the oil bodies in the mature cells. The author believes that mito- 

 chondria exist and are normal constituents of the cytoplasm, but regards evidence as to their 

 division and their function in heredity as inadequate. The mitochondrial origin of chloro- 

 plasts is discussed, but author takes no definite position thereon. — E. W. Sinnolt. 



1943. Yamaha. [Rev. of: Weatherwax, P. Gametogenesis and fecundation in Zea 

 mays as the basis of Xenia and heredity in the endosperm. Bull. Torrey Bot. Club. 46: 73-90. 

 1919. See Bot. Absts. 2, Entry 717.] Bot. Mag. Tokyo 33: 165-166. 1919. 



ECOLOGY 



H. C. Cowles, Editor 



1914. Andrews, E. F. The Japanese honeysuckle in the United States. Torreya 19: 

 37-43. -fig. 1919. — Lonicera japonica Thunb., until recently known in this country only as 

 a cultivated plant, has escaped widely in the eastern United States, especially in the South, 

 its range extending from Texas to Massachusetts. It spreads very rapidly by runners, and 

 smothers out other vegetation. Under these conditions it rarely flowers, but propagates 

 chiefly by vegetative means. — /. C. Nelson. 



1945. Arber, Agnes. Aquatic angiosperms: The significance of their systematic distri- 

 bution. Jour. Bot. 57: 83-86. Apr., 1919.— See Bot. Absts. 3, Entry 733. 



1946. Bar, Joh. Die Vegetation des Val Onsernone (Kanton Tessin). [The vegetation 

 of the Val Onsernone (Canton Tessin).] Ber. Schweiz. Bot. Ges. No. 26. 80 p. 1 map. 

 June, 1918. — A detailed account of the distribution of vegetation in the drainage basin of the 

 Isorno, Kanton Tessin, Switzerland. The area approximates 113 square kilometers and is 

 characterized by very rugged relief, being surrounded by mountain chains ranging above 

 2000 meters. Throughout the region ravines are so numerous as to leave very few flat areas 

 of any considerable size. Precipitation is high, averaging about SO inches and the greatest 

 rainfall occurs during the season of vegetative activity. The climate in general is decidedly 

 "Insubrian." The altitudinal distribution on northern slopes shows the following zonation: 

 chestnut 250-900 meters; beech 900-1100 meters; silver fir 1100-1600 meters; spruce 1600-1700 

 meters; larch 1700-2000 meters. On southern slopes the zonation shows an upward advance: 

 chestnut 250-1050 meters; beech 1050-1750 meters; larch 1750-2100 meters. Certain species 

 of oak, linden, birch and alder form distinct stands depending mainly on local climatic and 

 edaphic factors. Aside from the forest types the author describes the distribution and com- 

 position of the deciduous and coniferous scrub types; the meadow and heath types; the swamp, 

 moor and freshwater types; and the ruderal vegetation which is well developed in spite of 

 the barriers that tend to exclude it. [Unsigned full rev. in Jour. Ecol. 6: 235-239. 1918; un- 

 signed rev. in Nature 102: 243. 1918; rev. by Tubeuf in Nat. Zeit. Forst. Landw. 16: 358- 

 359. 1918.]— P. D. Strausbaugh. 



1947. Bennett, Arthur. Potamogeton acutifolius Link. Jour. Botany 57: 101. 1919. 

 On p. 17 of the same volume of this journal lat. 60° 12' n. was given as the northern limit of 

 this species. A specimen is now reported from lat. 62° 30' n. in Finland. — K. M . Wiegand. 



1948. Bowman, H. H. M. Botanical ecology of the Dry Tortugas. Carnegie Inst. Wash. 

 Publ. 252: 109-138. 6 pi., 7 fig. 1918.— The flora of these eight small coral islands is essen- 

 tially a strand flora determined by the uniformly xerophytic conditions which prevail. In 

 this flora four fairly distinct associations are recognized: (1) the Uniola community; (2) 

 the Suriana community ; (3) the Opuntia community; and (4) the Chamaesyce community. 



