HORTICULTURE. 949 



together with synonyms oi the difft'rt'nt varieties and the seed firms who have 

 offered them to the trade. 



The new rhubarb culture, J. E. :\Iokse and G. B. Fiske [Xcw York: Orange 

 Judd Co., 1901, p)>. l.'.O, fujs. 57).— This work gives in a clear and concise manner 

 specific directions for tlie winter forcing of rliubarl) in cellars, pits, hotbeds, cold 

 frames, and greenhonses. The field culture of rhubarb is also dealt with at length, 

 the methods of many practical rhul)arb growers being quoted and sunnnarized, and 

 the work of the experiment stations with varieties and methods of growing rhubarb 

 reviewed. A chapter is devoted to methods of cooking rhubarb and preserving for 

 winter use. 



The book of the greenhouse, J. C. Tall.vck {London and Xnv York: John Lane, 

 1901,})]}. 103, figs. 7(5).— This is the second of the series of handbooks of practical 

 gardening edited by H. Roberts. It contains short practical chapters on the structure 

 of greenhouses, the culture of hard-wooded plants in the greenhouse, climbers and 

 basket plants, bulbs, plants from seeds, foliage, and miscellaneous greenhouse plants, 

 with a chapter on a small town greenliouse. 



The fuel question in greenhouse heating, L. R. Taft {Anier. Gard., 22 {1901), 

 Nos. 347, pp. 569, 370; 349, pp. 602, 603; 350, p. 622).— In this article a discussion is 

 given of the theoretical value of different fuels, the efficiency of different types of 

 boilers, and the coal required for greenhouse ranges of different sizes, etc. 



A study of certain conditions aflPecting the setting of fruits, E. S. Goff 

 ( ]V'm-onf<in Sia. Rpf. 1901, j)p. 289-303, figs. .^(9).— The work here reported with fruit 

 is mainly from the standpoint of the pollen grain. With the Prunus apple, George 

 Glass cherry, and seedling native plum, the anthers failed to burst in a saturated 

 atmosphere under a bell jar after 56 hours, while in dry air the anthers on duplicate 

 twigs had practically all burst. The experiment indicates that during periods of 

 protracted rain, or so long as the trees are wet with rain or dew, or enveloped in fog, 

 practically no anthers burst, and therefore no pollen is wasted. Even in damp, cloudy 

 weather it is not likely that much pollen will be destroyed. Other experiments with 

 blossoms placed in a refrigerator and kept in the laboratory indicate that pollen is 

 discharged freely only in warm and dry weather. 



In order to learn the influence of the weatlier ujion the germination of pollen grains, 

 a number of germination experiments in 3 per cent milk sugar solutions were made. 

 Temperature was the first factor investigated, the germinative power of plum, cherry, 

 apple, i:)ear, raspberry, and strawberry pollen, as affected by temperature varying from 

 39 to 70° F. lieing noted. Drawings showing the germination of the pollen grains on 

 microscopic slides are given for each of the different fruits. The Moldavka plum 

 germinated as well apparently at 51° F. as at 65 to 70° F. Wood plum, however, 

 germinated more freely at 65 to 70° F. than at any lower temperature. Dyehouse 

 cherry germinated at 40° F. rather more freely than jjlums did. Pear pollen failed 

 to germinate at 40° and showed only a feeble germination at 51° F. Prunus apple 

 pollen germinated very slightly at this temiserature. Strawberry pollen germinated 

 rather freely at 51° F. but failed to germinate at 40° F. Pollen of King Amarelle 

 cherry and Lombard and Wood plums, exposed to a temperature of 51° F. for 6 

 days in a saturated atmosphere under a bell jar, germinated rather freely in sugar 

 solutions, while iiollen exposed to the temperature of the laboratory for the same 

 period failed to germinate. These facts indicate that the vitality of pollen is not 

 likely to be injured by exposure to a prolonged rainy period if the weather remains 

 cool. If it rises to 65 or 70° F. the vitality of the pollen may l)e destnjyed. 



Experiments to determine the effects on pollen of exposure to frosts were not sat- 

 isfactory. The pollen of plum and cherry germinated slightly after exposure to 28° F. 

 and the pollen of Wallace raspberry freely after exposure to 23° F. 



The influence of the vigor of gnjwtli of the terminal Ijuds of the cherry as related 

 to the setting of fruit was studied, and some figures are given which show the whole 

 number of the flowers that were produced on spurs which made a terminal growth 



