40 CIRCULAR 16 8, U. S. DEPARTMENT OF AGRICULTURE 



The scolytid Xyleborus nitobei (133) may be considered as a 

 secondary pest in Taiwan in that its attacks largely follow those 

 of other borers, principally cerambycids, and healthy trees are sel- 

 dom affected. One generation is produced each year, the adult 

 beetles appearing in August, and the eggs are laid in crevices in 

 the bark of injured areas. 



The scarabaeid beetle Ectinohoplia rufipes feeds quite extensively 

 during the early part of the season upon the blossoms and young 

 foliage of citrus in Chosen. As far as known this is the southern 

 limit of its range, which extends northwards to Manchuria and the 

 Amur region. A related species, as yet undetermined, has been 

 noted feeding at the blossoms in central Honshu. 



The list of fruit flies of the family Trypetidae comprises three 

 species, and of these Deceits tsimeonis (59, 98, 135, 11$% which was 

 discussed in some detail by the writer in a previous paper (11), is 

 apparently limited in distribution to certain parts of the island of 

 Kyushu. The late Doctor Miyake, who described the species origi- 

 nally, asserted that Japan was its native home but later came to the 

 conclusion that this is not the case. It has not as yet been recorded, 

 however, from any other country. D. bezzii, though often found 

 in the vicinity of citrus groves in Japan, is not known definitely 

 to attack the fruit. The adults are at times found swarming about 

 overripe persimmons on the trees. 



Dacus diversus var. formosanus (133, 169) is a minor pest of 

 orange in Taiwan, the most severe infestations seldom exceeding 

 5 per cent of the crop. In addition to citrus the mango is one 

 of the fruits frequently attacked. The number of generations pro- 

 duced each year has not been determined, but there are presumably 

 four, and the greater part of the winter is passed in the larval 

 stage within the fruit. 



The Formosan orange fly, Ohaetodacus 1 ferrugineus var. dorsalis 

 (80, 83), is recorded as occurring in Taiwan, the Philippine Islands, 

 Burma, Ceylon, and India, and is also reported from Okinawa (59). 

 Professor Maki's excellent account of this species deals at length 

 with the life history, habits, and methods of control. Every species 

 of citrus grown in Taiwan was found to be attacked, although the 

 greatest injury was to pomelo and citron. The fruits other than 

 citrus that are attacked are Fortunella spp., mango, peach, pear, lo- 

 quat, guava, Eugenia jam&os, and E. javaniea. In India it is also 

 recorded by Fletcher in the fruits of Capsicum frutescens and So- 

 larmm verb as ci folium, and in Ceylon from S. irwlongena. 



There are presumably three full generations each year under Tai- 

 wan conditions, with breeding more or less continuous throughout 

 the year, though much retarded during the winter season. Additional 

 generations may be produced in case suitable fruits are available for 

 attack. The minimum duration of the egg, larval, and pupal stages 

 was found to be 2, 12, and 2 days, respectively, with the maximum 

 during the winter of 20, 46, and 41 days. The periods of greatest 

 abundance of the larvae in the fruit were found to be in June and 

 September, with the greatest scarcity from late April to the middle 

 of May. Adults may be found throughout the year, but in greatest 

 abundance from June to September. 



