PLANT HYBRIDIZATION BEFORE MENDEL 275 



c. Wilson. 



In a paper entitled "The structure of certain new hybrids 

 (Passiflora, Albzica, Ribes^ Begonia^ etc.),'' John H. Wilson re- 

 ported, to the meeting of the Hybrid Conference in London in 

 1899, the following data regarding the structural character of 

 hybrids in species of the above genera. Inasmuch as this consti- 

 tutes another one of the few pre-Mendelian attempts at the meas- 

 urement of the characters involved in hybridization, the results 

 are given in some of the principal cases, as follows : 



Branches 



Passiflora buonapartea X -P- coerulea 



9 Stout, tetrago- $ Almost cylin- 

 nal-winged. light drical ; 5-6 well 

 green defined angles ; 



glaucous-green 

 with reddish 

 purple 



F, hybrid. 

 Stouter than the 

 9 and more angu- 

 lar; about 5 an- 

 gles. Much pur- 

 ple coloration. 



Leaf-blades 



Large, ovate- 

 cordate, some- 

 what acuminate : 

 dorsal, dark 

 green; ventral, 

 lighter green ; 

 8 5/8 in. long ; 

 7 1/4 in. broad ; 

 entire 



5-, often 7-lobed, Invariably 3 

 by branching of lobed, 7 1/2 in 

 the two lower 

 lobes ; occasion- 

 ally 3-lobed ; dor- 

 sal, deep green ; 

 ventral, glaucous. 

 Minute marginal 

 glands at leaf 

 notches, near 

 base of lobes ; 

 5 in. long; 7 3/8 

 in. broad 



long, 10 3/4 in. 

 wide at tips of 

 lobes. Average 

 length, 5 1/4 in. 

 X 7 1/2 in. 



Leaf 



Passiflora alba X P- buonapartea 



Long-ovate, cor- 

 date, somewhat 

 acuminate ; en- 

 tire. 8 5/8 in. 

 long, 7 1/4 in. 

 wide 



Lamina, 3-lobed. 

 6 in. long, 6 1/2 

 in. wide. Petiole 

 3 1/4 in. or 

 more 



3-lobed, 6 in. 

 long, 7 in. wide 



No. of flowers 

 in inflorescence 



Ribes nigrum X R. grolsularia 

 7-8-13 1-2 



Av. 3 



Ovarian glands 



Sessile, O.15-O.17 

 mm. diam. 



0.1 mm. diam.; 

 stalks 1.2 mm. 

 long 



0.1-0.13 mm. 

 diam., length of 

 stalk. 0.03-0.13 

 mm. 



