218 



substauoe for an animal substance. As soon as this process is completed both the 

 caterpillar and the fungus die, and become dry and hard, l)ut Avithout shriveling 

 at all. The thing is then a wooden caterpillar, so to say, with a wooden* bulrush 

 standing up from its neck. 



In China the head of the bulrush is gathered, carefully tied in little bundles, and 

 sold at a high price for medical purposes. The native physicians use it in cases of 

 diseases of the throat and lungs. 



The accompanying flgures illustrate the parasitized grub in the earth 

 (Fig. 24) and a commercial bundle of larv« and fungi. The first is copied 

 from a drawing sent by Mr. Jones, and the second is drawn from the 

 specimens themselves. 



THE DIFFICULTY OF DISINFECTING IMPORTED PLANTS. 



On page 441, volume iii, we published an account of certain experi- 

 ments with date palms introduced by the Pomologist of the Department, 

 in which we endeavored to eradicate the scale insects with which the 

 plants were infested. We there showed how great was the difficulty in 

 eft'ecting a complete extermination of the scales by means of the insec- 

 ticide washes which are so successful in the orchard. We notice that 

 Mr. Alexander Craw, of California, in imrsuance of his duties as quar- 

 antine officer, has been having the same difficulty Avith regard to the 

 scales upon orange trees imported from the Sandwich Islands. It is 

 stated in the California Fruit Grower of August 1st that after fumigat- 

 ing four times with hydrocyanic gas the scales were not all killed. 

 The writer of the note in the California paper deduces from this fact 

 the conclusion that if this repeated application of the most i)owerful 

 of our "disinfectants" does not entirely destroy the scale on nursery 

 stock there is little chance of eradicating the same pest in orchards, 

 and that the only panacea for this is to be found in nature's own rem- 

 edy, the parasites. He seems to have overlooked the point, however, 

 that these scales upon more or less dormant trees during shipment are 

 themselves to a certain extent dormant and much more than normally 

 resistant and that the same application which failed to destroy these 

 would undoubtedly prove more efficacious in the growing orchard. 



A very fidl report of Mr. Craw's experiments and the difficulty which 

 he had in performing his duties on account of strenuous objections from 

 the consignees is given in the Pacific Rural Press of September 12. 

 The whole matter was thrown into the courts and a decision was reached 

 that the trees should remain in quarantine until the owners could prove 

 that they were clean. The scale insects infesting these particular trees 

 were determined by Mr. Craw asfoUows: Mytilaspis citricola, Lecaninm 

 hesperidum, Aspidiotus rapax Aspidiotus limoni, Aspidiotus sp. near j^ci^s, 

 Parhitoria sp., Bactylopius citri, Chionaspis Mclavis. Of these the 

 Dactylopius and Chionaspis were found the most difficult to kill, the 

 latter being a mining scale. 



