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PROCEEDINGS OF THE THIED ENTOMOLOGICAL MEETING 641 



numbers but not regularly. This pest is rather attracted to Acacia 

 sp., and the tea-plant ; on the former it often occurs in great numbers 

 so that theie are no green leaves on all the trees in a small area, e.g., 

 in the year 1910 at Pankio in Taihoku-Cho, in 1912 in a certain district 

 of Shinchiku-Cho and Kagi-Cho, and in 1914 at Ako. In those cases 

 Acacia-trees were almost always withered by the attack of this 

 insect. 



The wingless female is fertilized by the male in the case, the long 

 protrusible abdomen of the male penetrating into the female-case from 

 above. Eggs are laid in the case, the female gradually shrinking up as 

 the eggs fill the lower portion of the case. The number of eggs deposited 

 by a single female is about 40 to 150, each egg being roundish and pale 

 whitish yellow. One to three weeks after the eggs have been laid the 

 caterpillars hatch and soon after they emerge from the parent's case 

 and make their own little cases of vegetable matter and interwoven 

 silk ; these cases are extremely tough and durable, and are spindle- 

 shaped. At first the young larvae spin a rather broad ring formed of 

 small pieces of finely divided under-epidermis of a leaf woven by means 

 of a fine silkj thread sent forth from their mouths, and then they place 

 their head in the ring-hole and thus the body becomes covered with the 

 ring cloth. The larvse, after the first moult, grow to about twice or 

 more in length. Afterwards the larvae bearing the complete case wander 

 to take more pieces of leaf for their case, here and there, and the cases 

 are gradually formed completely, with small pieces of leaf (or only of 

 the under-epidermis). The caterpillars eat the leaves from the under- 

 side, in an irregular shape, and when fully fed the cases are firmly 

 attached on to the under-side of the mature leaves or young twigs or 

 other suitable places. After a few days the larvae in such a case moult 

 and then the head and thorax emerge at the upper end of the cases. 

 Again the larvae wander here and there to seek their food or some covering 

 matter for their cases. After repeating the above, the larvae become 

 full-grown, and the cases grow very large clothed with several large 

 pieces of leaves and a few leaf-stalks or short (about 12 mm. long or 

 less) pieces of young twigs. At last the full-grown larvae firmly fasten 

 their cases almost always on the twigs and pupate in them. The larvae, 

 in the last instar, are blackish brown ; the head is rather semicircular, 

 and bears a few fine hairs ; the dorsal thoracic somites are pale yellow- 

 ish, on the middle there is a blackish longitudmal stripe from the 

 first to the second, which is inconspicuously divided into two lateral 

 stripes by a fine whitish middle stripe, while at the side there are irre- 

 gular blackish brown flecks. The abdominal portion on each somite 

 bears 8 — 10 shining tubercles from which spring fine hairs. The legs 



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