284^ 



The Journal of Heredity 



their apices. It can be seen that dichog- 

 amy is not so pronounced that autog- 

 amy is not possible. The proteran- 

 drous anthers are often eaten by insects 

 or birds (?) and the pollen is thus 

 prematureK- discharged. 



The base of the corolla tubes, espe- 

 cially those of the large flowering 

 species, is usually filled with great 

 numbers of Brachypeplus (small insects 

 with short wings) and the Drepanid 

 birds may find in them a source of 

 insect food. Dr. Perkins seems not to 

 have mentioned that fact, though he 

 has often, on being invited, picked ofif 

 specimens of Brachypeplus from dried 

 herbarium specimens of the rarer and 

 new Hawaiian Lobelioideae. When one 

 breaks flowering branches of Cyaneae 

 or Clermonliae especially those with 

 large flowers, the inflorescences become 

 alive with Brachypeplus as well as small 

 Carabidae. 



We can judge from these remarks 

 that the Lobelioideae must certainly 

 belong to one of the oldest groups of 

 plants inhabiting this archipelago. 

 Long before there were any Drepanid 

 birds the Lobelioideae must ha\e oc- 

 curred in these islands, to be sure not 

 in such numbers, but perhaps in iso- 

 lated individuals with structural char- 

 acters probably different from those 

 which are now existing. Since the 

 Drepanid birds themselves show a 

 relationship to American birds, we 

 must look to the ancestor of the 

 Drepanideae of today as the possible 

 agent of dispersal of the baccate 

 Lobelioideae. That the Drepanid birds 

 and Lobelioideae had a more or less 

 simultaneous development can again 

 be surmised by the fact that in some of 

 the Drepanid birds we still find indi\id- 

 ual variation as regards the length of 

 the bill. —7. F.Rock. 



A SECTORIAL CHIMERA IN MAIZE 



IN THE rainy season of the last year 

 1920, some true breeding varieties 

 of maize were sown on the farm 

 of the Agricultural College, Poona, 

 (Bombay Presidency, India), some 

 crosses were made between these 

 varieties. There was one cross between 

 two varieties from the Department of 

 Agriculture — Kashmir State, (north- 

 ern India). The two varieties con- 

 cerned were Canadian Red No. 5 and 

 amber pearl pop corn No. 8. One cob as 

 a result of the cross was collected. 



The seeds of this cob were sown in 

 the cold weather of 1920. Out of a 

 large number of plants grown from the 

 seeds of this cob, there is one single 

 plant which shows this phenomenon: 



The fully grown plant is six feet 

 tall and has one tiller. All the leaves, 

 young and old, of this plant have one 

 half of their laminae bisected by their 

 mid-ribs bearing >ellow and whitish 

 stripes. The leaf sheaths and stem are 

 also half striped. The striped halves of 

 laminae, leaf sheaths and stem are all 



T. R. Khadilkar, B. Ag. 

 College of Agriculture, Poona, India 



on one side of the plant. The tiller also 

 has similar stripes. 



The appearance of these stripes on 

 one vertical half of the whole plant 

 appears to be a case of a sectorial 

 chimera. The accompanying photo- 

 graph shows the stripes on the lea\-es 

 very clearly. 



One cob on this plant is selfed and 

 it is to be seen in the next (F2) genera- 

 tion whether seeds of the selfed cob 

 breed true in this character or whether 

 the character disappears altogether. 

 It is expected that Fo generation will 

 throw more light on the nature of this 

 chimera. 



In Genetics in Relation to Agricul- 

 ture by Babcock and Clausen (page 381) 

 it is stated that, "variegated foliage 

 which is caused by factor mutations 

 causing complete or partial chlorophyll 

 reduction are also fairly common 

 among Snapdragon, four-o'clock, ge- 

 raniimi and maize plants. The varie- 

 gated character can be transmitted to 

 sexually produced offspring." 



