314 



emerged in 14 days. This work must be carried on unceasingly until 

 no more cocoons are to be found in the plantation. The parasites 

 are to be maintained at the end of the operation by collecting attacked 

 pods, laying them in heaps and covering them thickly with cacao 

 leaves. In two or three days a quantity of cocoons will be obtained, 

 and the pods and cocoons should be hung up in the parasite examination 

 shed and the cocoons subjected to the same process of examination 

 as those collected from the plantations. The method appears to be 

 laborious, but an intelligent native can be taught all that is necessary 

 and men trained by the central station are sent to those plantations 

 which need them and cannot secure their own. The plan works best 

 on a plantation of moderate size. Any excess of parasites may be 

 collected and sent to plantations that need them. Proper control by 

 the central station is very necessary, to see that the work is done by 

 competent persons and that the hyperparasites are properly sorted 

 out and destroyed. If the method were universally adopted the author 

 thinks that, under well-defined conditions, " rampassen " operations 

 might be replaced by parasite propagation. 



Keuchenius (P. E.). De Biologie van eenige Kofflecicaden. [The 

 Biology of some Coffee Fulgoridae.] — Meded. Besoekisch Proefst., 

 [Dj ember, Jam], no. 13, 1914, pp. 1-8, 2 pis. [Received 3rd March 

 1915.J 



Two Fulgorids, the black and white Lawana (Poeciloptera) Candida, F., 

 and Pochazia fuscata, F., are here dealt with. Two years ago Dr. Wurth 

 noted in the reports from the Experiment Station at Malang that 

 certain plantations were invaded to an alarming extent by L. Candida, 

 Coffea robusta, Lamtoro (lead tree), Hevea and dadap {Erf/thrina) being 

 especially affected ; later reports showed that great damage had been 

 done by the insects sucking the juices of the young plants. Dadap was 

 the most attacked, Coffea robusta came next, and then Lamtoro and 

 Hevea. The eggs are laid on the leaf ribs and stems, cuts being made by 

 the female in which she lays her eggs in regular rows, the total number 

 amounting to several hundreds. A figure is given of a section of a 

 dadap twig showing that the bast is so thin that the ovipositor reaches 

 the cambium ; the eggs are covered by an outgrowth of the epidermis 

 which forms a kind of lid to the cut. Careful examination of a line 

 of eggs laid on the midrib of a C. robusta leaf showed no damage to 

 the vascular bundles, as the covering parenchyma forms a sufficiently 

 thick protection. The egg stage appears to last about three weeks ; 

 the larvae are entirely covered with a white, woolly, waxen material 

 which remains for months on the trees after the insects have left. 



Pochazia fuscata, F., is practically unknown to the planters and is 

 not even mentioned in the literature of the Dutch East Indies, but 

 at the beginning of 1914 it invaded the coffee plantations of one 

 district in such numbers as to be a veritable plague ; a nmch smaller 

 outbreak occurred in the previous year, but no notice was taken of it. 

 P. fuscata has only made its appearance in any numbers on one 

 plantation, and in this almost exclusively on Coffea robusta, a few only 

 occurring on dadap. On the coffee the eggs were laid on the leaf 

 veins on the under side, and on dadap on the stems. The two species 

 can readily be distinguished with the naked eye in the egg stage. 



