342 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



VARIATIONS OF FLOWERING SEASONS. 



Fritsch has lately published the result of an investigation 

 into the variations of the seasons of flowering of plants in 

 different countries in the same year and in different years, 

 and, basing his conclusions upon fifty-two plants and twenty- 

 three stations, he remarks that the variations of the seasons 

 of flowering are greater as this time naturally falls in the 

 earlier part of the year. Thus, of plants flowering in March, 

 the variation will amount to thirty-seven days, while of those 

 flowering in June it amounts only to twenty-four days. These 

 variations, again, are, on an average, as great in positive sea- 

 sons as in negative that is to say, the acceleration of the 

 flowering season, on an average, of each plant investigated, is 

 as great as the retardation ; and it is only necessary to divide 

 the entire variation by two in order to obtain the deviation, 

 whether positive or negative. 19 C, February 10, 1872, 48. 



PREFERENCES OF CLIMBING PLANTS. 



According to Mr. Henry, certain climbers evince a partial- 

 it y for some particular species of plants, stretching out their 

 tendrils and branches so as to come in contact with them, 

 while to other species they have as decided an aversion, 

 avoiding them, and never becoming attached to them, though 

 they run up the surface of the wall side by side. 12^4, Jan- 

 uary 4, 1872, 192. 



A THREAD ALGA IN THE STEM OF A DICOTYLEDONOUS PLANT. 



Dr. Reinke, in making cross sections for microscopic exam- 

 ination of a stem of a plant known as Gunnera scabra, found 

 a blue-green spot, which he discovered to constitute the cross 

 section of a bluish-green thread alga, belonging to the genus 

 Scytonema, and hence called S. gunnerce. This was com- 

 pletely inclosed in the parenchyma of the stem, and separa- 

 ted from the upper surface by a thick cellular stratum. 19 

 <?. February 10, 1872, 47. 



ALG^E OF RHODE ISLAND. 



Mr. Stephen T. Olney, a well-known botanist, resident at 

 Providence, Rhode Island, has just published a list of the al- 

 gse of Rhode Island, as collected and prepared by himself. 



