368 



Mr. Hulst adheres to bis belief " that there must be very extensive 

 fertilizatioa of the dehisceut species of Yucca by the afjencies of bees 

 aud other iusects." He does not briug forth a single delinite fact or 

 observation of actual pollination to prove or sustain the belief, but rests 

 it on the following grounds: 



1st. That Meehan found that the mere application of pollen to the 

 papillose apex of the stigma is sufficient for fertilization. 



2d. That he (Hulst) has seen honey-bees within the open as well as 

 the partly open flowers, as also other insects, Aphides aud Coccinel- 

 li(l;e being particularly mentioned. 



3d. Tliat not one in ten of the capsules subsequently examined by 

 him showed the larva. 



4th. Tliat he is informed that dehiscent species of Yucca do ripen 

 seeds in Europe. 



Such are the negative arguments upon which rests his belief in the 

 face of all the facts I have put on record. Let us consider the former 

 briefly in their order. 



1st. My good friend Meehan has written much on the fertilization of 

 Yucca — much, too, that has not shown the keenest penetration nor the 

 strictest ascuracy. But, in candidly admitting his errors when shown 

 to be wrong (as he has done to the writer, and, I have reason to believe, 

 to Mr. Hulst, who sought his support in the belief here combated), he 

 has proved himself to be the true naturalist. I am familiar with his 

 experiments, having witnessed the results, and can best express my 

 own opinion by quoting from a letter from the late Dr. G. Euglemanu 

 (written January 10, 1881), in which, among other things, he says: 



As to Meeban's operations, I liav^e seeu myself the fine, large, well-filleil pods of 

 Yiuca angiistifuUa raised by biui by bis artificial method. He says he liuuches an 

 anther into the stigraatic cavity. Whether he or anybody else could distinguish 

 whether the pollen adheres only to the papillose (not stigmatose) apes or gets into 

 the liquor that fills the cavity when the stigma is ready to conceive, is a question (or 

 no question) ! 



Meehau's experiments were made on a species in which, as I have else- 

 where shown, the stigma is shorter and the stigmatic liquor more abun- 

 dant than in Yucca filamentosa^ and it may be that for these or other 

 reasons it is more easily pollinized by hand or by other means than by 

 Proiiuba. But I have followed up his experiments, aud made many 

 others during the past seven years, on Jilamentosa and aloifoUa, with 

 results that convince me that application of the pollen to the papillose 

 apices only is not sufficient to insure fructification, at least in those 

 species. My experiments have been made in the afternoon, evening, 

 aud morning, with flowers one day, two days, and three days after 

 opening; with pallen from the same flower or from other flowers either 

 on the same or other racemes, by touching the mere apices with anther 

 or brush, and byforcing the pollen by either conveyance into the stig- 

 matic tube. In these experiments, which have not yet been published, 

 and which it is unnecessary to detail here, I have endeavored to guard 



