16 AUSTEALTAN SUGAR CANE BEETLES AND THEIR ALLIES. 



liowever, there is a continual loud hum about the feeding-trees, due ta 

 the fact that all the beetles move, either in search of mates or for exercise 

 and better foliage on which to feed during the night. 



Morning Flight. 



I have been informed by observant growers on several occasions 

 that the beetles llew into the cane at daybreak, supposedly to oviposit, 

 and, furthermore, I also found the following note by Girault in our 

 file:— 



"Gordonvale, December 23rd, 1911. At half-past one this morning 

 I took up a position at the edge of a cancfield adjoining a forest; the 

 night was clear but moonless and pleasant. While darkness lasted I saw 

 jio ])eetles, nor heard any. At 5 o'clock, however, a single beetle was 

 observed flying into the cane from the forest; five minutes later a 

 half-dozen more were observed to do this, in an irregular manner exactly 

 similar to their flight from the cane to the forest at dusk. All of these 

 beetles alighted in the cane after about fifty yards, but none could be 

 followed, and this flight lasted but for a very short time ; it was not light 

 until about twelve minutes later. I could find no beetles in the forest 

 from whence they came. Were these ovii)Ositing females, leaving the 

 cane to feed in the night or on a night when this is convenient to them?" 



Fortunately, Mr. Uodd was able to practically clear this matter up 

 while at Greenhills during the fortnight 23rd January to 4th Februai-y, 

 1920. On clear mornings he found that the fligiit started about 4.45 a.m.. 

 the beetles moving from the forest over the cane ; at first the flight was 

 clearly defined, but toward its conclusion the beetles began whirling 

 low over the cane, and many were seen to settle on the leaves where they 

 remained quiet for some time; but they had disappeared by noon, sup- 

 posedly into the soil, for in one instance he observed a beetle drop to 

 the ground and commence to dig at 9 a.m. 



The writer was able to verify these observations during the 1920-21 

 season. Morning after morning I went into a field of cane near the 

 laboratory between 4 and 5 o'clock. The sky was clear, with bright 

 moonlight. Each time the beetles began to come from the feeding-trees 

 to the east and south-east as soon as the sky lightened a little. At exactly 

 5 o'clock I saw the first one coming from the direction of the place where 

 the sun was soon to appear, a little to the south of east. In a few 

 minutes dozens were coming, all from the same quarter. Their flight 

 was rather steady and regular, about 10 to 12 feet over the cane, and they 

 went as far as the eye could see against the skyline to the west and 

 north-west, right to the back of the farm, which had invariably been an 

 infested area, though located fully half-a-mile from these feeding-trees 

 to the east. Going to the part of the field where the beetles were settling 

 I found them circling downward rather erratically, each one finally 

 landing with head up on a cane-leaf, which swung down with its weight. 

 I watched many of them and this was invariably the case. The morning 

 flight constantly ended before 5.30, and the air became noticeably quiet, 

 especially after the incessant hum that the beetles made when moving 

 in such numl)ers. 



Just after the flight one morning I watched six of the beetles that 

 had settled near together on the cane-leaves. 



No. 1 fell to the ground at 6.30 and dug in under the stool. 



No. 2 fell off at 6.45 and crawled under the stool before digging in. 



