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THE AMERICAN BEE JOURNAL. 



corpuscuulm is so far from facilitat- 

 ing the introduction of the pollinia 

 that it prevents the part to which it is 

 attached from being again caught in 

 the slits ; and, until the movement 

 occurs, the corpusculum with its two 

 pollinia will pass over the entrance 

 to the stigmatic chamber without be- 

 ing injured. 



After the movement occurs, if the 

 corpusculum be examined from one 

 side, it will be observed that the 

 retinacula project outward and down- 

 ward. Since the parts to which the 

 corpuscula are attached themselves 

 project outward and downward, the 

 retinacula tinally stand nearly at right 

 angles to the leg of the insect. The 

 retinaculum, near the point where it 

 joins the pollinium, is bent rather 

 suddenly, so that the pollinium ap- 

 pears to be flexed upon it. This flex- 

 ure, which Mr. W. H. Leggett has 

 called the knee, is very prominent. 



There is quite an interval between 

 the knees and the membrane of the 

 retinaculum at the knee is expanded 

 . transversely to the plane of the pol- 

 linium. Robert Brown has observed 

 in A. purpurascens, that the part of 

 the retinaculum extended between the 

 knee, and the pollinium remains at- 

 tached to the latter when it is found 

 in the stigmatic chamber. This ex- 

 pansion of the membrane serves to 

 prevent the withdrawal of the pollin- 

 ium after it has been inserted into the 

 cavity, and, when drawn against the 

 closely opposed edges of the ate in 

 the upper part of the stigmatic cham- 

 ber, facilitates the rupture of the 

 retinaculum. 



Judging from the structure of parts 

 which are readily caught between the 

 anther-wings, nothing could be more 

 natural than for one of the knees to 

 slip into the entrance to the stigmatic 

 chamber, and the movement is in- 

 tended to turn them into such a posi- 

 tion that this will occur. When, 

 therefore, the movement has taken 

 place, and the insect draws its leg 

 over the angle of the wings, the cor- 

 pusculum with the claw or hair to 

 which it is attached, passes on with- 

 out being caught, while one of the 

 knees of the pollinia readily enters 

 the stigmatic chamber, and the pol- 

 linium enters with it. When the 

 knee has reached the upper part of 

 the cavity, and will go no further, the 

 retinaculum is torn across and es- 

 capes, leaving the pollinium in posi- 

 tion to effect fertilization. 



In repeated trials at artificial pol- 

 lination of the flowers of A. Cornuti, 

 A. Sullivantii, and A. incarnata, I 

 succeeded three times, in the case of 

 A. Sullivantii, in separating the pol- 

 linium from the retinaculum without 

 withdrawing the latter from the slit, 

 and thus was enabled to insert a pol- 

 linium, and to draw out a corpuscu- 

 lum at the top of the ulaj with its two 

 pollinia by the same movement. But 

 in all other cases a pull that seemed 

 sufficient to break the rectinaculum 

 freed it from the slit so that the cor- 

 pusculum at the top remained intact. 

 Accordingly, I have seen nodifliculty, 

 on the supposition that the pollinia 

 are introduced by the knees, in the 

 observation of H. MuUer, who says : 



" In several flowers which I dis- 

 sected, the corpuscula and pollen 

 masses were still in their places, 

 though pollinia, which must have 

 come from other flowers, had been in- 

 serted into the stigmatic chamber." 



In a number of cases observed by 

 me on A. Sullivantii, the movement 

 which turns the knees toward the 

 flower is completed in about seven 

 minutes, though it has proceeded 

 sufficiently in five minutes to turn the 

 flexure far enough to render its in- 

 sertion quite likely. With the view 

 of pollination stated in this paper, 

 the slow movement is plainly of ad- 

 vantage, because a knee can hardly 

 be caught by the wings until it has 

 occurred. 



Now, since only one pollinium is 

 inserted into the stigmatic chamber, 

 there is an economic disposal of the 

 pollinia. The interval between the 

 flexures is so great that only one of 

 them can be caught, while the other 

 passes by the slit uninjured. There 

 are, therefore, two chances of a pol- 

 linium being transferred to another 

 plant. If both pollinia were left at 

 each act of pollination, there would 

 be hut one chance of cross fertiliza- 

 tion. Moreover, the chances of cross 

 fertilization would be reduced from 

 the fact that the stigmatic chambers 

 would be more nearly filled by pollinia 

 from the same source, while if they 

 are.introduced singly, there are more 

 chances of a chamber receiving a pol- 

 linium from a distinct plant. 



As two pollinia are fastened to- 

 gether, there would be but one chance 

 of pollination occurring if the pollinia 

 were inserted by the corpuscula, while 

 there are two chances of a knee being 

 caught. When a pollinium has been 

 removed, the broken retinaculum may 

 be caught in a slit and remove a sec- 

 ond corpusculum with its two pollinia. 

 When this combination of two cor- 

 puscula and three pollinia is drawn 

 over the angle of the wings, there are 

 three chances of a pollinium being 

 caught. Whenever a pollinium is re- 

 moved, two new pollinia may be sub- 

 stituted for it, and a large combina- 

 tion of pollinia may result, arranged 

 either in a unilateral series or dicho- 

 tomously. In either case, the chances 

 of the insertion of a pollinium equals 

 the number of pollinia in the combi- 

 nation. 



If the foot to which the first cor- 

 pusculum of the combination is at- 

 tached must enter the stigmatic 

 chamber, of course there would be 

 but one chance of pollination taking 

 place without regard to the number 

 of pollinia. Such an accident would 

 be likely to destroy the whole combi- 

 nation. As already observed, on the 

 large flowers of A. Sullivantii and A. 

 Cornuti, the shorter hairs on the legs 

 of insects are not readily caught, so 

 that the number of parts to which the 

 corpuscula may be attached are re- 

 duced to the minimum. 



For instance, the only parts of the 

 leg of a hive-bee which can remove 

 the corpuscula of these species, are 

 the two claws and the pulvillus. The 

 leg will thus remove three corpuscula, 

 and since these bodies render useless 

 the parts to which they are attached, 



the broken retinacula not only take 

 the place of the parts disqualified, but 

 increase the number of parts to which 

 the corpuscula can be attached. By 

 means of these combinations, there- 

 fore, the leg of an insect has its 

 capacity for carrying pollinia greatly 

 increased. . . 



Finally, I have seen the pollinia of 

 A. Sullivantii introduced into the 

 stigmatic chambers in the manner 

 described. The pollinia and the en- 

 trance to the chamber in this species 

 are very large and are easily seen, and 

 hive- bees move so slowly in effecting 

 pollination that, after a knee is. 

 caught, one can see the pollinium 

 slowly disappear between the wings,, 

 so that there can be no doubt as to 

 the manner of insertion. Commonly, 

 however, the insertion of pollinia oc- 

 curs so rapidly that it is impossible to 

 see how it really happens. After a 

 pollinium has been introduced into 

 the chamber, hive-bees always have 

 difticulty in breaking the retinaculum, 

 and they lose their lives on account 

 of this as well as on account of the 

 difliculty in drawing their clawa 

 through the slit. When a foot is held 

 by a retinaculum the pollinium i» 

 found in the chamber, with every in- 

 dication that it was introduced by the 

 knee. 



Blackburn University, Chicago, 111. 



[The foregoing article was sent to 

 us by Mr. J. M. Valentine, of Carlin- 

 ville. Ills., being "advance sheets"' 

 of the Botanical Gazette for October, 

 1887. It will be read with great in- 

 terest by those who heard the ad- 

 dress of Prof. Cook at the Chicago 

 convention on " The legs of the bee," 

 and also by all who are interested in 

 learning the relation which bees sus- 

 tain to the blossom and the fruit. Mr. 

 Robertson is professor of botany at 

 the Blackburn University in this 

 city.— Ed.] 



Vor the American Bee JoamaL 



ResDlts oftlie Season Of m 



J. M. CLAKK. 



I commenced the season of 1887 

 with 23 colonies in fair condition, 

 which built up very strong during 

 fruit bloom. The honey season opened 

 very encouragingly, but from some 

 cause, even before the drouth com- 

 menced, the honey-flow slackened up. 

 White clover bloomed abundantly, 

 but yielded very little honey. Bass- 

 wood bloomed very full, but before 

 we could realize its presence, it was 

 gone. We were having quite a 

 "bonanza" on sweet clover, there 

 being about two acres of it. . It is 

 growing along one of the railroads, 

 but just as we were exulting in our 

 good fortune, the railroad olBcials 

 had it all cut down. 



The fall flowers yielded some very 

 nice white honey after the rains com- 

 menced, but we did not get any buck- 

 wheat honey. 



