388 ANNUAL OF SCIENTIFIC DISCO VERY. 



consulted and studied. No less than 120 authors' names are attached to the 

 430 species described in the present volume, and upward of 1000 volumes 

 will have to be referred to before the " Flora" is completed. A large propor- 

 tion of the plants of India have, moreover, proved identical with those of 

 other countries, and in every large genus the authors have had to make a 

 critical study of the European, Siberian, Chinese, and Japanese floras, elicit- 

 ing results of interest totally unexpected, and of the highest importance in 

 their bearings on the science of botanical geography. 



FLAX AXD KEMP CULTIVATION IK EUROPE. 



The importance of the rettery system of treating flax, as enabling the 

 grower to sell his flax-crop without becoming involved in the processes of 

 steeping, drying and scutching, is evidenced in the fact that large retteries are 

 now at work in England, Scotland, France. Belgium, Holland, Austria, Prus- 

 sia, and Bavaria. Fourteen steeping establishments are now in operation in 

 Ireland, carrying out the modern patented methods of treatment. In some, a 

 portion of the straw is steeped in open-air tanks, but all of them press the 

 flax-straw between rollers after its removal from the steep, and from this 

 treatment the fiber shows a marked improvement. The present unmechanical 

 process of scutching seems to be now getting some improvement, for the 

 attention of very many inventors has been drawn to the subject. The govern- 

 ment returns show the number of scutching-mills in Ireland, in 1852, to have 

 been 1,056; there having been, in 1852, but 956 mills. The Belgium Instructor 

 reports thus on the growth of hemp: "From personal observation, I have 

 arrived at the opinion that hemp can be only grown profitably in Ireland in 

 the following manner: It should bo sown after potatoes, the field being 

 thoroughly cleansed while digging that crop. The hemp-crop can be followed 

 by a flax crop. The hemp should receive some artificial manure such as 

 guano, or rape-cake ckist at the sowing period, to create a quick stimulus to 

 the young plant, the manure to be applied with the seed. The seed should 

 not be sown either broadcast or in drills, but with the usual wheat-sowing 

 machine, and covered crossways with tho roller ; or better still, plowed in, in 

 the same way as wheat, along with the artificial manure, so that the crop 

 will be in drills of three or four inches apart. As only 140 plants at most aro 

 required per square yard, and each pint contains 10,570 seeds, it follows that 

 32 quarts would be sufficient quantity of seed per statute aero : but I would 

 recommend an increase of one fourth that quantity for the following reasons : 

 Experience has shown clearly that, although the female plant is the most 

 vigorous at tho ripening period, the male plant will take the lead until it 

 arrives in blossom : that the male forms about one fourth of the whole crop, 

 and possesses little fiber, and that of inferior quality, reaching maturity fully 

 four weeks before that of the female. By pulling the whole crop at the ripen- 

 ing period of the female, the male plant becomes valueless. By taking a 

 medium that is, two weeks after the ripening of the male, and two weeks 

 before that of the female the valuable seed is sacrificed, and the straw steeps 

 unevenly, with a mixed fiber of inferior quality. To obviate these evi]?, a 



