158 Journal of Agricultural Research vo1.xvi.no.6 



found under loose bark and the beetle remained with its ovipositor in 

 the crevice for one and one-half minutes. During this time there was a 

 perceptible pumping motion near the basal end of the ovipositor, and 

 4 eggs were laid in an irregular row. The tree is attacked anywhere 

 from the large aerial roots to high up on the trunk, but usually in the 

 middle trunk. 



THE EGG 



The egg (PI, 19, C) may be compared in shape to a scallop ohell, and 

 one end, which is broader than the other and flattened, is irregularly 

 ribbed. It is white and ranges from 1 to 1.5 mm. in length; the average 

 width is approximately 0.75 mm. 



The red mangrove has the bark separated into plates; in the process 

 of growth loose bark occurs at the dividing lines (PI. 19, C). The eggs 

 are inserted under this thin outer layer of loose bark in an irregular longi- 

 tudinal row. Four eggs are the largest number that have been found 

 together. Eggs occur singly and in twos and threes. One female may 

 lay eggs in several trees. Twenty-three full-sized eggs were dissected 

 from one female, many eggs being in the distended oviduct, and many 

 immature ovules were present. 



The period of incubation was not determined but probably one week 

 is required. Young larvae 5.5 mm. in length were found on April 23, 

 1 91 8, in a red mangrove tree near Miami Beach. 



THE LARVA 



The larva^ is white and a typical " flatheaded" borer (PI. 20, B; fig. i). 

 It is of the common Chrysobothris type, moderately compressed, and 

 sparsely covered with coarse, light-colored bristles. The first thoracic 

 segment is large and oval; the second wider and shorter than the third; 

 the third wider than the first abdominal, which is narrower than the 

 second abdominal ; the third to eighth abdominal are of about equal width, 

 the ninth and tenth successively narrower; the lateral folds of the 

 second to ninth abdominal segments are well developed ; the dorsal plate 

 of the first thoracic segment is marked with a well developed, inverted 

 V of grooves and pointlike rugosities; the ventral plate has a well devel- 

 oped groove extending back three-fourths of the distance from the ante- 

 rior margin, and rugosities which tend to form ridges. The length is 

 30 mm. and the width of the first thoracic segment 7 to 8 mm. 



The young larvae upon hatching from the eggs bore through the 

 cambium to the surface of the wood and as they feed on the cambium 

 and grow they extend the burrows horizontally, spirally, or longitu- 

 dinally (Pi. 20, A). The entire length of the burrow is packed with 

 boring dust. The length of the larval period is nearly one year. When 



' Description by Mr. H. E. Burke, Bureau of Entomology. 



