216 



MR, A. M. ALTSON ON THE LIFE-HISTORY AND 



Hosts. — The species of larvje used in this work and from which 

 A. manducator Panz. was successfully bred, are as follows : — 



Lacilia sericata Meig. 



ccesar Liun. 

 Phormia grmnlandica Ztt. 

 Calli'phora erythrocephala Meig. 

 vomitoria Linn. 



No preference was shown for any individual species, the 

 odour of the putrefactive juices being the chemotropic stimulation 

 to oviposit; and therefore it is probable that other carrion- 

 feeding cyclorhaphous larv?e would he found to be suitable hosts. 



In this connection Marshall (3) states: — "They have been 

 reared from various maggots, as Lucilia ccesar L., Cyrtoneura 

 stahulans Fall., Hydrotea dentipes Fab." 



Life-History and Habits of Xasoxfa BUEvicrmNJS Ashm., 

 AND Hosts. 



Historical. — Nasonia hrevwornis Ashm. was first described by 

 Girault and Saunders, 1909 (6). They bred it from the puparia 

 of the Common House-fly (Musca domestica Linn.) at the Illinois 

 Entomological Station at Urbana in 1908. It has since been 

 reported from Chili and India, and was bred in 1911 from the 

 puparia of C. erythrocephala Mg. by Graham -Smitli (1) at 

 Cambridge, England. In November 1913 it was bred from the 

 puparia. of Pycnosoma rufifacies by McCaithy (2) at the Govern- 

 ment Sheep-fly Experiment Station at Yarrawin in New South 

 Wales, and a few days later discovered at Longreach, Central 

 Queeufsland (7). As already stated, page 197, it was first bred 

 by the writer from the puparia of C. erythrocephala collected 

 from Regent's Park, London, in July 1919. 



Introductory. — In the following account of the life-history and 

 habits of this insect, the writer freely quotes from the writings 

 of the previous observers, adding here and there observations of 

 his own. In doing this the writer desires to put forward as 

 general and collected an account of this important insect as 

 possible ; further, it may be observed that the writer had already 

 made an independent study of this subject before specimens were 

 identified and the original description of Girault and Saunders (6) 

 brought to his notice. Full acknowledgment is made to these 

 references, which for the sake of the continuity of the account 

 are mostly signified by reference numbers only. 



The Length of the Life-cycle. — This is entirely dependent upon 

 the temperature, and its influence aff'ects the full-grown larval 

 stage the most. 



The various observers differ as to the period of the life-cycle, 

 but this can be accounted for by the probable differences in 

 temperature when the observations were made. Girault and 

 Saunders (6) give 22^ days as the average in the spring and 

 15 days in autumn ; McCarthy (2) 11 days in summer ; Froggatt 



