| Abstract: | Summary
Helopeltis antonii was bred at different constant temperatures at the experimental station at Semarang in 1939 and 1940. Some of the results concerning the duration of development from hatching of the egg untill the imaginal stage are recorded in the table and the graph. By comparing these data with those published byLeefmans (1916) (Helopeltis bred on tea in West Java) andZehntner (1901) (Helopeltis bred on cocoa in Central Java) we find that the time of development mentioned by these authors is shorter. In accordance with the experiments ofBonnemaison (1946) this probably can be attributed to the breeding ofHelopeltis at alternating temperatures (day and night). The duration of development at 19°C, mentioned byLeefmans (19 days), however, differs so much from the duration found in this investigation (32–34 days) that this explanation seems improbable. Other experiments at constant temperature, that will be published elsewhere, show that the population used for breeding was well adapted to the average temperature at the estate, Djati Rungo, from where this population came. This extreme adaptation suggests that this may also occur at other localities. Therefore it is probable that the populations ofH. antonii from different localities do not have the same genetical composition. The differences mentioned above can probably be attributed therefore to this fact. Data are given to strengthen this supposition. The existence of genetically different populations has already been suggested by ProfessorRoepke in 1909. He called them  biological races . The occurrence of the varietybradyi ofH. antonii is probably caused by such a difference too and thus could better be considered as a subspecies.Helopeltis theobromae
Mill. is without doubt only a subspecies ofH. theivora.Thus we suggest:Helopeltis antonii subspec.bradyi
Wat.
new comb.
Helopeltis theivora subspec.theobromae
Mill.
new comb.
Deventer |
