108 



breeding of Aphids in the tropics occurs as a continuous series of 

 parthenogenetic generations. Even in the hills, where the temperature 

 sometimes drops to freezing point, the author did not observe sexual 

 forms ; nor was a regular migration, such as may be noted in Eiurope 

 in the spring in the case of PEMpniGiNAE, observed in Java ; but this 

 point is not definitely settled. Alate forms probably occur in all tropical 

 Aphids. They are mostly present at the beginning of or during the 

 dry season, but many examples are also to be found during the rainy 

 season. Most European investigators maintain that the alate forms 

 are due to the drying up of the food-plant, but that this is not always 

 correct is proved by the appearance at the end of the dry season, 

 and only then, of some Aphids living on bamboo foliage and belonging 

 to the genus Oregma, Buckt., such as 0. insularis and 0. striata. In 

 the case of species such as 0. minuta, the alate forms are not uncommon 

 early in August, i.e., in the middle of the dry season. In Java the 

 majority of Aphids are most numerous early in the dry season, and 

 both prolonged, intense drought and violent rainfalls injure them. 

 Variations in she.ter, as afforded by different host-plants, are of great 

 importance in this connection, and the species liviag on bamboo 

 foliage are most common at the end of the rainy season. Natural 

 enemies include SjT^phid larvae, Coccinellids, especially the genus 

 Scymnus, and Ichneumonids. These appear to be the main factor in 

 checking the increase of Aphids. 



Descriptions are given of 75 species, of which 47 are recorded as new 

 to science. Several generic and specific keys and a list of food-plants 

 are included. Only two species are recorded as injurious : — Oregma 

 lanigera, Zehnt., on sugar-cane, and Myzoides persicae, Sulz., on 

 tobacco. 



Chukichi Harukawa & NoBUMASA Yagi. Ueber die Lebensweise 

 des Pfirsichtriebbohrers, Laspeyresia molesta, Busck. [The Life- 

 History of the Peach-shoot Borer, Cydia molesta.'] — Berichte 

 Ohara Instituts fur landwirtschtl. Forschungen; Kuraschiki, 

 Okayama, Japan; i, no. 2, 1917, pp. 151-170, 2 plates. 

 [Received 16th December 1918.] 



There are three species of Cydia (Laspeyresia) injurious to the 

 peach in Japan. Cydia pomonella, L., C. persicana, Sasaki, and 

 a third species which the authors consider to be identical with 

 C. molesta, Busck. The damage done by the last-named has attracted 

 attention since 1902. Sasaki began to investigate this pest, and later 

 on Matsumoto foimd that not only the shoots of the peach but also 

 its fruit and those of Pyrus sinensis (sand pear) are attacked. His 

 investigations have elucidated many points in the life-history. 

 According to him 4 generations a year occur in the province of Okayama 

 and towards the end of July the fruit of P. sinensis begin to be infested, 

 the attack being more severe in varieties that ripen late. In 1916 

 Takachiho published his investigations, and the present authors agree 

 with him and Matsumoto on the main points. C. tnolesta is distributed 

 throughout Japan, except in Hokkaido and the northern portions ; 

 it occurs in Korea, but not in the Loochoo Islands and Formosa. It 

 is believed nor to be a native of Japan, for the damage it does was not 

 noticed prior to 1899. Brief descriptions are given of the egg, larva, 



