New York Agricultural Experiment Station. 377 



No. 10. It is estimated that no more than 25 per ct. have 

 germinated. The growth is correspondingly less than in No. 9, 

 One of the longest tubes measured 27//. The tubes probably do 

 not average half that length. Oftentimes they are abnormally 

 bent and in many eases disintegration is seen. 



No. 11. This culture shows a network of long tubes. One 

 which was measured was 98.4//. long, but it cannot be said that 

 this is one of the longest of them. Only in a few cases can tubes 

 be traced through their entire length because they are so much 

 tangled, and a close estimate of their average length cannot be 

 made. It may be said, however, that they have made abundant 

 grow'th. 



No. 12. Pollen tubes are tangled so much that only in few 

 instances can they be traced throughout their entire length. 

 One measured 52.56/./., but others were certainly longer. The 

 average length is estimated as. considerably less than in No. 11. 

 Only occasional indications of disintegration were seen. 



POLLEN CULTURES IN MIXT RE B. 



The spray mixture which is here designated '' mixture B " was 

 simply a Bordeaux mixture made as for " mixture A," but it 

 did not have any arsenical poison added to it. A single anther 

 from a Ben Davis apple blossom was selected Llay 17 in the w^ay 

 previously described, p. 374, to furnish pollen for a series of 

 tests in which the growth of pollen in solution of sugar in water 

 might be compared witl. its growth in a similar suf-^r solution 

 combined with various proportions of the Bordeaux mixture B. 

 The following cultures were made at 5 p. m., May 17. They 

 were put into a room in which by means of an automatic appara- 

 tus the temperature was kept nearly constant at about 70° F. 



to 72° F. 



Series II. 



Number of pollen 

 Cnlture grains in the 



Ko. Medium. culture. 



4 2 per ct. aqueous solution cane sng-ar Several huudrod 



5 5 per ct. aqueous solution cane sugar Not recorded 



6 10 per ct. aqueous solution cane sugar About 250 



7 5 per ct. aqueous solution cane sugar, 95 parts; 



Bordeaux mixture B, 5 parts About 300 



8 2 per ct. aqueous solution cane sugar, 98 parts; 



Bordeaux mixture B, 2 parts Several hundred 



