368 ANNUAL KECORD OF SCIENCE AND INDUSTRY. 



140 feet liigb, and over 17 in circuit. The tallest tree in pro- 

 portion to its girth is the sweet gum, exceeding an altitude 

 of 160 feet, with a clear shaft of over 100 feet, and a maxi- 

 mum circumference of 17 or 18 feet. The honey locust at- 

 tains a height of 120 feet, the red maple exceeds 100, and 

 even a sassafras has been measured with a height of 95 feet. 

 5 7>, 1872, 658-665. 



PKOPAGATION OF THE MISTLETOE. 



The English mistletoe (Viscimi album) grows abundantly 

 through the southern countries of England, but is almost en- 

 tirely confined to the orchards. This is readily started by 

 rubbing the fruit upon the bark of the tree, when the muci- 

 lage which covers the seeds causes their adhesion, and if the 

 season be sufficiently moist, they take root upon germination, 

 and the young plant attaches itself at once to the branch. 

 Several attempts have been made to introduce into England 

 the Loranthus Europceus^ a similar parasite which frequents 

 the oaks of Austria and other parts of Southern Europe. Dr. 

 Moore has at length succeeded in some measure by bruising 

 the soft bud gently upon a young oak-shoot of the previous 

 year, and inserting in its centre the seed of the mistletoe. 

 Seeds thus planted in January, 1870, germinated in the 

 spring of the following year, and the resulting plants are 

 yet living. The Garden, 1873, 81. 



HABITS OF DKOSERA. 



Mr. Ziegler has lately been making some studies upon the 

 cilia of the Dr'oseras, or sun-dew plant, which, as is well 

 known, exude from their tips a viscous secretion by which in- 

 sects are secured. Whenever an insect is thus taken, the ex- 

 ternal cilia bend round and cover the insect, as if in the 

 clasp of the hand, and do not relax their hold until at the 

 end of several days, when they open, in order to secrete mu- 

 cilage more and entrap a new prey. It is an interesting fact 

 that albuminated animal substances, under ordinary circum- 

 stances, will not exercise any evident action upon the cilia 

 of the plants in question ; but if they are held a few minutes 

 between the fingers, they acquire the property of causing the 

 cilia to contract. If, however, these same animal substances 

 are then moistened with distilled water and dried in a sand 



