36 REPORTS OF OBSERVATIONS AND EXPERIMENTS. 



During July of the present year these larvae were again very numerous, 

 as well as the mature flies upon the same plant, and many were bred 

 from larvae inclosed. While the larvae of these flies prey upon all 

 sorts of Aphidids in Australia and are frequently found upon those 

 on orange and corn, this is the first time that I have observed them in 

 California. 



During July of 1891 many of the eggs of Selandria cerasi examined 

 upou young pear trees were found to be infested with a parasite, while 

 others showed holes from which parasites had issued. 



Xotes on an introduced Australian Ladybird. — Since reporting upon 

 the recently introduced Rliizobius vent rails Gr. I have made further 

 notes which may be of interest. A colony of these beetles received 

 from Hon. Ellwood Cooper and liberated by Mr. S. F. Leib, of San Jose, 

 upon Leeanium olece infesting prune trees July 23, 1893, were examined 

 August 23 of that year, and numerous half-grown larvae were found. On 

 looking over the same trees September 22, only a few grown larvae could 

 be found, yet pupae were numerous. At my own place a few of the 

 mature insects were liberated upon Physiantlius alba infested with L. 

 oJew August 21. Grown larvae were here observed October 6, and on 

 the 17th of the same month many pupae were present. One of the 

 females liberated upon this plant August 21 was still present and lay- 

 ing eggs. The same conditions were found at two other places in Ala- 

 meda where this insect had been colonized upon black scales. As this 

 Ehizobius will breed during the entire year, fully six broods can be 

 expected in the southern part of the State. The mother beetle will 

 deposit her eggs under the older Coccids in numbers. Often an entire 

 scale is found conrpletely filled with the eggs of the Ehizobius. After 

 the young larvae issue they remain under the scales and devour eggs 

 and Coccids before leaving. The plants may be full of young larvae, yet 

 these are seldom seen, since they most always remain under the older 

 scales and feed upon the contents. As they become larger they can 

 occasionally be noticed Avalking around while feeding, yet are found 

 more numerous hidden away between curled-up leaves and even 

 among spider webs, where many pupate. If liberated upon any bush 

 or tree infested with Leeanium, a gravid female will at once begin to 

 oviposit, and will not leave the plant as long as there is sufficient food 

 for the offspring. 



While looking over a lemon tree infested with Leeanium olece and L. 

 liesperidum, upon which this Ehizobius had been liberated August 21, 1 

 was agreeably surprised, not only in finding large numbers of the same 

 in all stages, but also B. debilis Black, that had been liberated in my 

 yard upon Aspidiotus pemiciosus by Mr. Craw during May of 1892, 

 The tree mentioned i£ about one-half mile distant from the original spot, 

 where the same insect can still be found. 



