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SCIENGK 



[N. S. Vol. XI. No. 269. 



The structure and reproduction of Compsopogon : 

 De. Eoland Thaxtbr, Harvard Univer- 

 sity. 



The author gave some account of the dis- 

 tribution of Compsopogon in Florida, men- 

 tioning the localities where it had been 

 found by himself and others, in fresh as 

 well as partly tidal waters. Its general 

 structure was described, attention being 

 called to the fact that the older filaments 

 may possess a cortex of from two to four 

 layers of cells. Details of cell structure and 

 the normal reproduction by aplanospores 

 were illustrated, as well as the formation 

 of small aplanospores developed from sorus- 

 like groups of superficial cells. 



On some diseases of Neiv England Coniferce : 

 Db. Hermann von Scheenk, Shaw School 

 of Botany. (By invitation.) 

 The coniferous woods of this region are 

 being destroyed by the mycelia of a number 

 of fungi, chief among which are, Polyporus 

 tenella, Polyporus Schiveinitzii, Polyporus pi- 

 ceinus, Polyporus pinicola, Polyporus sulfureus 

 and Agaricus melleus. The mycelia bring 

 about characteristic changes in the wood 

 either by destroying the lignin and leaving 

 pure cellulose, or by transforming the wood 

 into a brown brittle substance. The changes 

 are caused by enzymes one of which was ob- 

 tained from Polyp)orus tenella, capable of de- 

 stroying the substance hadromal, leaving 

 pure cellulose. This enzyme is not diastase. 

 The extent to which decomposition is car- 

 ried on is apparently determined by de- 

 composition products such as humus com- 

 pounds, citric and succinic acids and others. 

 These stop the action of the enzyme at a 

 certain point. The enzyme transforms 

 the wood in great quantities ; many pounds 

 of pure cellulose are often found in one 

 place. Masses of cellulose and some ha- 

 dromal were exhibited. The mycelia of 

 these fungi live both as parasites and sapro- 

 phytes, some entirely in the ground. The 



sporophores of many excrete manitose in 

 quantity at the time when the spores are 

 ripe. This may aid in the dissemination 

 by attracting bark beetles. Six forms of 

 wood destruction were described, and speci- 

 mens and photographs of the same were 

 shown . 



Vegetative reproduction and multiplication in 

 Erythronium : Mk. Feederick H. Blod- 

 GETT, New York Experiment Station. 

 (By invitation.) 



The presence of underground runners in 

 Erythronium americanwn has been recognized 

 for some time. The development of the 

 runners, and especially of the bulbs which 

 are formed from their terminal buds was 

 published in 1895. In the present article 

 the author describes the common origin 

 within the bulb of these runners and of the 

 annual bulbs of the mature individuals, as 

 axillary buds between the base of the stem 

 and the inner bulb scale. The develop- 

 ment of the first bulb from the seedling is 

 also described. It is characterized by con- 

 taining the plumule instead of the normal 

 foliage leaf and remains latent for a year. 

 From one bulb, thus developed from a seed, 

 the life cycle is shown to occupy not less 

 than four years, probably six or seven years 

 in most instances. During this interval 

 runners are given off each year, usually 

 three annually, resulting in a bed in five 

 years of from six to nine plants for each 

 seed, or ninety plants if ten seeds of a 

 single fruit should survive all steps of the 

 cycle. 



Current problems in Plant Cytology : Profes- 

 sor J. M. Macfarlane. (Presidential 

 Address. ) 



This address is expected to appear in ab- 

 stract in Science. 



The structure of starch grains : Dr. Henet 

 Kraemee, Philadelphia College of Phar- 

 macy. (By invitation.) 

 In the different text-books starch grains 



