339 



the host. In one case a male of Tarsonemus {sens, sir.) was found 

 in the trachea of a bee, proving that more than one species of mite 

 of this family may enter the respiratory system of Apis mellifica. 

 A species of Tarsonemus has also been found in Apis dorsata. 

 A.florealis and A. mellifica var. indica from India. 



Taubenhaus (J. J.). A Study of the Black and the Yellow Molds of 

 Ear Corn. — Texas Agric. Expt. Sta., Colles^e Station, Bull. 270, 

 October 1920, 38 pp., 10 plates. [Received 10th May 1921.] 



An investigation into black mould ( Aspergillus niger) and 

 yellow mould (^4. flavus) has revealed that the former invariably 

 starts on maize at the point where an insect, especially the corn ear- 

 worm, Heliothis [Chloridea] obsoleta, has penetrated through the husk 

 into the ear. The insect in feeding produces a considerable quantity 

 of moist excrement that offers an excellent medium for A. niger. 

 In young, tender ears the fungus spreads rapidly to the entire inner 

 surface, but in partly ripened ears infection will remain localised 

 within the feeding area of the insect. Thoroughly ripened ears are 

 seldom infected, for at this stage they are practically free from ear- 

 worms. There are other insects, as well as rodents and birds, that 

 may open the way to infection by A. niger. Experiments have 

 proved that H. obsoleta frequently carries on its body spores of A. 

 niger and A. flavus. Both organisms are also frequently found on 

 cotton bolls that have been attacked by H. obsoleta, and A. niger 

 also on tomatos injured by this moth, though it does not seem to 

 cause decay so long as the fruit is in a green and growing condition. 



Since A. niger can only invade maize during the milky stage, and 

 after attack by H. obsoleta, it follows that the disease will be most 

 prevalent in seasons when the caterpillars are most numerous, that is, 

 generally speaking, in dry seasons, and also that the remedy for black 

 mould is control of the corn ear- worm. Cultural methods will check 

 the numbers of H. obsoleta to a great extent, and the cultivation of 

 varieties of maize that are inattractive to the insect is recommended. 

 As a preventive against yellow mould, only those varieties of maize 

 that have pendant ears should be planted, especially in localities with 

 a heavy rainfall. 



Smith (H. S.). Biological Control of the Black Scale in California. — 



Mthly. Bull. Cal. Dept. Agric, Sacramento, x, no. 4, April 1921, 

 pp. 127-137, 5 figs. 



Saissetia oleae, Bern, (black scale) is the worst pest of Citrus in 

 California, where it is widely distributed. This scale has been largely 

 controlled by fumigation with sodium cyanide, but the enormous 

 expense of this method and of the washing of the fruit, and the 

 apparent decrease in effectiveness of recent fumigations, has 

 indicated the desirability of substituting control by means of natural 

 enemies. An attempt was made in 1913 to introduce parasites from 

 South Africa, but their establishment was unsuccessful. Aphycus 

 iounsburyi, one of the most important parasites occurring in Africa, 

 has, however, since been introduced from Australia, thus forming a 

 sequence of natural enemies with the Coccinellid, Rhizobius ventralis 

 and the egg-parasite, Scutcllista. Two insectaries have been estab- 

 lished for the rearing of A. Iounsburyi. It was found that the method 

 of handling the parasite must be made to correspond with the seasonal 



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