i SCIENCE AND INDUSTRY. 
PARASITES OF THE BLACK SCALE, 
The black scale (Saissetia olew) is not considered to be a pest of prime 
importance on citrus trees in Australia. Whether this is due to the natural 
enemies of the insect established in that country the writer does not know, 
but various ornamentals such as pittosporum, oleander and elm were at times 
heavily infested in the botanic gardens at Adelaide and Melbourne. In the 
citrus groves visited by the writer only an occasional tree was seen to be 
infested to any extent. On these trees the predacious moth, Thalpochares 
cocciphaga, the internal parasites, Coccophagus sp., and Aphycus lounsburyii, 
the egg-parasite, Scutellista cyanea, and various ladybirds were found in 
abundance. : 
The two internal parasites, Aphycus lounsburyii and Coccophagus sp., were 
collected at Parramatta and Gosford, both in New South Wales, and were 
received by the Insectary at Sacramento in living condition. As climatic 
conditions here are similar to those where these parasites were collected, there 
should be no difficulty in getting them established; particularly Aphycus, which 
seems to be the more promising. 
The Insectary force is now engaged in rearing these parasites in suflicient 
numbers to permit the introduction of them in California orchards. 
One of the most important enemies of the black scale in Australia is the 
predacious moth, Thalpochares cocciphaga. The larva of this moth feeds on 
all stages of the black scale, but seems to prefer the eggs. It is a 
case bearer, making a case of the remains of the host, under which it 
moves along the twigs in search of additional prey. As it breeds under 
conditions similar to California we can see no reason why it should not 
do well here. It is heavily parasited in Australia. A number of full- 
grown larve of Thalpochares were collected at Parramatta, New South — 
Wales, just prior to the writer’s departure from Australia, and placed in cold 
storage on board the ship. From these, seventeen moths were reared at the 
Insectary. They were confined in large test tubes and fed with honey. Eggs 
were first deposited on 16th July. On 24th July the first larve emerged. As soon 
as possible“ after emergence the larve were placed on citrus cuttings heavily 
infested with black scale, egg-stage. The cuttings were inserted in potato 
tubers to prevent their drying out too rapidly. As soon as the larve ate the 
eggs from one lot of cuttings they were transferred to another until they 
reached maturity, when they were removed to a vial to await emergence as 
adults. Other methods of rearing were to place the larve on oleanders infested 
with black scale and in vials filled with black scale eggs. All were successful. 
The first adult of the new generation emerged on 9th September, a little over - 
three months after their arrival. The new generation gives promise of a large 
increase in numbers, and we hope that two or three generations more in the 
laboratory will be sufficient to enable us to introduce them in the groves. The 
Thalpochares is the most promising of any of the material brought from 
Australia, 
PARASITES OF MBALYBUGS. 
No specimens of the citrus mealybug, Pseudococcus citri, were taken during 
the writer’s visits in the citrus orchard§ of Australia. A species closel 
resembling citri was found infesting a broad-leaved ornamental in the Botanic 
Gardens at Brisbane, Queensland. From this mealybug the Sicilian mealybug 
‘parasite, Paraleptomastix abnormis was reared. This parasite is the one 
which the Insectary Division collected in Italy some years ago, and which the 
Insectary has successfully colonized in the citrus orchards of Southern California. 
This parasite was undoubtedly introduced from Italy into Australia through the 
importation of plant material infested with mealybugs parasitized by this little 
insect. 
Only two other species of mealybugs were taken on citrus trees, Pseudococcus 
longispinus and Pseudococcus sp., the last being larger than any of our citrus- 
infesting species. None of these three mealybugs are considered to be at all 
destructive; in fact, in the Epping and Gosford districts of New South Wales 
a two days’ inspection of the orchards revealed only two groves to be infested. 
Most of the young mealybugs in these groves were parasitized. Just prior to 
the sailing of the steamer the writer spent a day collecting parasitized mealy- 
bugs. Approximately one hundred. specimens were taken. From these, two 
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