lo. 1. ] 



Misceliaiieons Nutrs. 



19 



In September 1890 were received throug'h the Agricultural Depart- 

 ment of Bombay^ earterpillars of a microlepidopterous insect reported by 

 Paiii Borer in Thana. the Collector of Thana 



to have done a con- 

 siderable amount of 

 damage to paddy 

 during the past two 

 years in his district. 

 The specimens were 

 insufficient for absolute 

 determination, but 

 were either identical 

 with, or very closely 

 allied to, the Rice Stalk 

 Borer (6'/n7o ort/sosellus) 

 of the United States. 

 A very similar insect 

 has been described as 

 destructive to paddy in 

 Perak, thoug'h it has 

 not yet been ascertain- 

 ed whether the species 

 found in Perak is 

 identical with that 

 which occurs in the 

 United States. With 

 regard to remedies, 

 the observations of 

 Mr. Howard in the United States, and of Mr. Wray in Perak, have shown 

 that the insect passes the time between the harvest of one year, and the 

 springing up of the crop of the following year, in the self-sown padd}^ 

 and perhaps also in the stems of large grasses, which spring up in and 

 around the paddy fields. The careful destruction therefore of these by 

 burning has been thought to be the most promising means of reducing 

 the numbers of the pest. According to Mr. Wray, eggs are laid in batclies 

 at the base of the leaves, 600 eggs being sometimes laid by one female. 

 These eggs hatch a few days after they are laid, and the caterpillar at 

 first feeds on the leaves, but after a short time it bores its way into tiie 

 inside of the stem, where it passes the rest of its caterpillar existence. 

 The chrysalis is formed either in the leaf stalk or inside the stem. A 

 generation takes about two months ; so, there are several generations In 

 the course of the year. (The figure shows the caterpillar, natural size and 

 enlarged, together with a piece of rice straw tunnelled by it.) 



c2 



