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S. spontaneum — and as every variety of cane grown at the station was 

 attacked, it is probable that all are susceptible ; even Black Cheriton, 

 which is supposed to be immune, suffered. The sugar-cane stem-scale 

 is covered practically throughout its whole life by a rounded white 

 shield of a waxy consistency, and is to all intents and purposes immobile, 

 remaining attached by its mouth- parts to the surface tissue of the cane. 

 Almost the only movement made by the insect is that necessary for 

 the larva to extricate itself from the egg ; it moves but little from the 

 place on which it was hatched and attaches itself almost immediately. 

 Propagation is rapid and abundant ; every female lays 60-80 eggs 

 and maturity is reached in 4 or 5 weeks, so that the gravity of an 

 attack is readily understood. The pest is found almost exclusively 

 on the stems ; occasionally it occurs on the leaf sheath or at the base 

 of a leaf, but appears rarely to mature in these positions. It is generally 

 noticeable about February, the joints becoming hidden with a 

 thick white covering. The wiping process is costly and not satisfactory, 

 because large numbers of the insects are left on the upper parts of the 

 canes behind the leaf sheaths, and in some fields it is the practice to 

 cut off the tops if they are badly infested. The natural enemies of the 

 scale are of the greatest importance to the planter. Chilocorus melan- 

 opthalmus, Muls., is peculiarly voracious and devours the scale more 

 or less completely. The eggs are laid under the shield, usually one to 

 each scale. The larvae hatch in 7 days, begin their work the moment 

 they emerge, and continue it for about 10 days, when they are full-grown 

 and pupate ; five days later the imago appears. This Coccinellid in 

 Java does not confine itself to C. tegalensis, but also attacks C. sacchari- 

 folii, Zehnt., boring one or two small holes in the shield and apparently 

 dragging the scale-insect through them. It has also been found feeding 

 in company with Aleurodes longicornis, Coccus viridis {Lecanium viride), 

 Green, Aphis sacchari, Zehnt., and Pseudococcus {Dactylopms) sacchari, 

 Cockerell, but these were not attacked. The destruction of C. tegalensis 

 is, however, remarkable. C melanophiliahmis is only occasionally found 

 in the coffee gardens, and is there apparently replaced by Orcus 

 janthinus, Muls. Two parasitic Hymenoptera have been found 

 attacking the scale and have been submitted to Mr. Girault for identifi- 

 cation. The attacked scales become hard and brown and are readily 

 recognisable. One species develops very rapidly, lays about 30 eggs 

 and reaches the imago stage in from 10 to 14 days, so that there is 

 reasonable hope of help from it in keeping down the scales, though, 

 owing to the mechanical conditions, it will be unable to reach those 

 on the tips of the canes. Besides these natural enemies, two other 

 Coccinellids, one a species of Scyninus, are perhaps of consequence. 

 The larvae of species of Chrysopa appear to frequent the scale- infested 

 canes, and the author has observed that certain caterpillars (one of 

 them he believes to be that of Euproctis minor) which ordinarily eat 

 the cane leaves, frequently gnaw away the whole of the shield of 

 the scale. The other is a grayish black hairy caterpillar which the 

 author was unable to identify. 



The presence of the scale has to be taken into serious consideration 

 in setting out a new plantation, as the scales may be introduced on the 

 sets or, according to Van Deventer, may in their very earhest stage be 

 carried by the wind ; this the author regards as only barely possible, 

 in view of the known facts as to the habits of the scale. Van Deventer 



