338 



SUMMARIES OF PLANT CHARACTERS, ETC. 



fore of the relative positions of the curves. The percent- 

 age of microscopic characters developed in excess of 

 parental extremes is precisely the same as the percentage 

 of macroscopic intermediate characters; and the com- 

 bined percentages of macroscopic and microscopic charac- 

 ters developed in excess and deficit of parental extremes 

 is much larger than the combined percentages of macro- 

 scopic and microscopic intermediate characters, the pro- 

 portions being 51.9 to 36.9. It is remarkable and inex- 

 plicable that the percentage of macroscopic characters 

 should exceed the percentage of microscopic characters 

 among intermediate groups and be the reverse in all of 

 the other five parent-phase groups. 



In Ltelia-Cattleya canhamiana (Chart F 2, Summary 

 1 of Table I, Part 2 and Summary 1) there is similar 

 gross correspondence and lack of correspondence in per- 

 centages and in curves, but the curves so differ from 

 those of Ipomaa sloteri as to be readily distinguishable. 

 In this hybrid the differences between the macroscopic 

 and microscopic data are, as a whole, distinctly more 

 marked ; the percentages of macroscopic characters are 

 less than those of the microscopic characters in 5 of the 6 

 parent-phases, the most marked difference being noted 

 among the characters that are developed in deficit of 

 parental extremes, while the percentages of both macro- 

 scopic and microscopic characters that are intermediate 

 are notably in excess of the percentages of characters fall- 

 ing under the other 5 parent-phases. Among the inter- 

 mediate characters, 52.9 per cent are macroscopic and 

 35.3 per cent microscopic. Taking the characters as a 

 whole, 40.3 per cent are intermediate and 34.4 per cent are 

 developed in excess or deficit of parental extremes. 



In Cymbidium eburneo-lowianum (Chart F 3, Table 

 I, Part 3 and Summary 1) the percentages of char- 

 acters differ, on the whole, only slightly more than in 

 either Ipomcea sloteri or Lcelia-Cattleya canhamiana. The 

 percentages of macroscopic characters are higher than 

 those of the microscopic characters in 3 and lower in 3 of 

 the six parent-phases, and the most marked differences 

 are found among the characters that are intermediate and 

 that are developed in excess and deficit of parental ex- 

 tremes. The percentage of macroscopic intermediate 

 characters is very much higher than the percentage of 

 microscopic characters (62.9 and 36, respectively) ; the 

 combined percentages of both macroscopic and micro- 

 scopic intermediate characters is close to one-half (44.6 

 per cent) of the total of all of the characters, and nearly 

 double the combined percentages (25.4 per cent) of char- 

 acters that are developed in excess and deficit of parental 

 extremes. It is extraordinary that while the ratio of 

 macroscopic characters that are intermediate to those 

 which are developed in excess and deficit of parental 

 extremes is 62.9 : 5.7, the ratio of microscopic characters 

 is 36 : 34.7. 



In Dendrobium cybele (Chart F 4, Table I, Part 4 

 and Summary 1) the percentages of characters differ 

 in degree, with one exception, from distinct to well 

 marked, the greatest divergence being noted among the 

 characters that fall under those which are the same as 

 those of the pollen parent, the same as those of both 

 parents, and which are developed in deficit of parental 

 extremes, especially the latter. In 3 of the 6 parent- 

 phases the macroscopic characters show higher percent- 



ages than the microscopic characters, in 2 lower per- 

 centages, and in 1 practically the same percentages. The 

 percentages of microscopic characters that are interme- 

 diate represent much more than one-third (43.3 per cent) 

 of the total characters and distinctly more than the com- 

 bined percentages (29.9 per cent) of characters that are 

 developed in excess and deficit of parental extremes. The 

 intermediate macroscopic characters represent a percent- 

 age (37 per cent) somewhat lower than the macroscopic 

 characters and distinctly lower than the combined per- 

 centages of characters developed in excess and deficit of 

 parental extremes (52.5 per cent). This inversed re- 

 lationship of the percentages that are intermediate and 

 developed in excess and deficit in comparison with the 

 macroscopic characters is extremely interesting. The 

 total percentage of intermediate characters is 37 in com- 

 parison with 46.6 per cent of characters developed in 

 excess or deficit of parental extremes. 



In Miltonia bleuana (Chart F 5, Table I, Part 5 and 

 Summary 1) there is a marked tendency to variation in 

 the distribution of percentages of macroscopic and micro- 

 scopic characters among the 6 parent-phases, the per- 

 centages being close in 3 and well apart in 3. The most 

 marked differences noted are in the percentages that fall 

 under characters that are the same as the seed parent, the 

 same as the pollen parent, and which developed in deficit 

 of parental extremes. The differences are not only well 

 marked, but much accentuated because of the relatively 

 small differences found under the other parent-phases. 

 The macroscopic character percentages are higher than 

 the microscopic percentages in 2 of the 4 parent-phases. 

 The macroscopic characters that are intermediate rep- 

 resent 31 per cent of the total characters, distinctly 

 higher than the combined percentages of characters de- 

 veloped in excess and deficit of parental extremes (17.2 

 per cent). The microscopic characters that are inter- 

 mediate show a somewhat higher percentage than the 

 macroscopic characters, but distinctly lower than the 

 combined percentages of characters developed in excess 

 and deficit of parental extremes, the ratio being 

 36.4 : 45.9, a reversal of values in comparison with the 

 macroscopic characters. The total percentage of inter- 

 mediate characters is 35.1 compared with the combined 

 percentages (38.7 per cent) of characters developed in 

 excess and deficit of parental extremes. 



The two Cypripedium hybrids C. lathianum and C. 

 lathianum inversum are offspring of reversed crosses. 

 In Cypripedium lathamianum (Chart F 6, Table I, Part 

 6 and Summary 1) the records are remarkable on ac- 

 count chiefly of the comparatively high percentages of 

 characters that are intermediate and that are developed 

 in excess of parental extremes, and the correspondingly 

 low percentages that fall under all of the other parent- 

 phases; the very marked differences between the per- 

 centages of macroscopic and microscopic characters that 

 are intermediate, and that are developed in excess of 

 parental extremes ; and the inversion of the macroscopic 

 and microscopic values in these two phases. The macro- 

 scopic percentages are lower than the microscopic per- 

 centages among the characters that are the same as those 

 of the pollen parent, developed in excess of parental ex- 

 tremes, and developed in deficit of parental extremes; 

 and lower in the other three phases. Among characters 



