ii8 



THE GARDENERS' MONTHLY 



[April, 



And now, after all this, a new scheme is before 

 Congress, called the " Dakota forestry bill," to be 

 championed by Mr. Pettigrew, under whi^h lands 

 in Western Dakota are to be sold to planters of 

 "twelve acres of timber," and so forth. It never 

 occurs to the wise men who project these schemes 

 that the planting of successful forests requires 

 knowledge and skill, which not one farmer in a 

 hundred is equal to, and that these twelve Acre 

 lots cannot possibly amount to anything of conse- 

 quence, even though a few are successful in solv- 

 ing the great forestry problem. 



But in truth it matters little, as we fancy, to the 

 "ground floor" projectors of these schemes, 

 whether any trees of consequence can by any pos- 

 sibility be made to grow in Western Dakota or 

 not; for is there not to be a "commission of three, 

 of whom two shall be practical (of course I) for- 

 esters ?" and their huge salaries will go on from 

 the passage of the act. 



It is a great pity that there is not head enough 



somewhere to get forests of a few thousand acres 

 apiece set out somewhere, with some such men as 

 Douglas or Sargent to supervise the whole ; and 

 there would be little need of forestry commissions, 

 whose only work is to write long-winded reports, 

 which nobody has any patience to read after Con- 

 gress has wasted thousands of dollars in publishing. 



L0MI5ARDIAN MuLBERRV Trees. — These are 

 the latest kinds offered. It should be remembered 

 by those engaged in silk culture experiments, that 

 all these new names mean nothing more than 

 mere varieties (and often barely that) of the com- 

 mon white mulberry. They are good enough in 

 their way. So long as nothing extra is paid for 

 the new name, people will not go wrong in buying 

 the plants. 



Valuable Seeds. — Seeds of the most valuable 

 varieties of. Cinchona bring $i,oco per ounce in 

 Ceylon. There are nearly 100,000 seeds in an 

 ounce. 



Natural History and Science. 



COMMUNICATIONS. 



Observations on the Fertilization of Yucca, and on 

 Structural and Anatomical Peculiarities in Pro- 

 nuba and Prodoxus.* 



BY C. V. RILEY. 



This paper records some recent experiments and 

 observations which establish, fully and conclu- 

 sively, the fact that Pronuba is necessary to the 

 fertilization of the capsular Yuccas. It describes 

 for the first time how the pollen is gathered and 

 collected by the female Pronuba. The act is as 

 deliberate and wonderful as that of pollination. 

 Going to the top of the stamens she stretches her 

 tentacles to the utmost on the opposite side of the 

 anther, presses the head down upon the pollen, 

 and scrapes it together by a horizontal motion of 

 her maxillae. The head is then raised and the 

 front legs are used to shape the grains into a 

 pellet, the tentacles coiling and uncoiling mean- 

 while. She thus goes from one anther to another 

 until she has a sufficiency. My observations con- 



*Abstract of a paper read at the Montreal meeting of the 

 A. A. A. S. 



firm the accuracy of Dr. Geo. Engelmann's con- 

 clusion as to the impotence of the stigmatic apices 

 in some of the Yuccas, and shows how the appar- 

 ently contradictory experience of Mr. Meehan can 

 be reconciled on variation in this respect in the 

 species of the same genus. The exceptional self- 

 fertilization in Yucca aloifolia — the only species in 

 which it is recorded — is shown to be due to the 

 fact that in the fruit of this species there is no 

 style, the st gma being sessile, and the nectar 

 abundant, filling and even bulging out of the shal- 

 low opening or tube. The flowers are always 

 pendulous, and the pollen falling from the anthers 

 can, under favorable circumstances, readily lodge 

 on the nectar. 



The irregularity in the fruit of the Yuccas — con- 

 sidered a characteristic by botanists — is proved by 

 experiment to be due to the punctures of Pronuba. 



The egg of Pronuba, which averages 1.5 mm. 

 long, having a swollen apical end, and a long and 

 variable pedicel, is passed into the ovarian cavity 

 of the fruit. The puncture is made usually just 

 below the middle of the pistil, on the deeper 

 depression which marks the true dissepiment, or 

 through the thinnest part of the wall. The horny 



