349 
ON THE LIFE-HISTORY OF ME LI TTOBIA ACASTA, 
WALKER; A CHALCID PARASITE OF 
BEES AND WASPS. 
By FRANK BALFOUR BROWNE, M.A. (Oxon. et Cantab.), 
F.R.S.E., F.Z.S., F.E.S., 
Lecturer in Zoology (Entomology) in the University of Cambridge. 
(From the Zoological Laboratory , Cambridge.) 
(With Plate XXVI.) 
CONTENTS. 
PAGE 
I. Introduction. 349 
{a) Material. 349 
( b ) Technique.350 
II. The Hosts of Melittobia .351 
III. Male and Female Characters.352 
IV. Life-history ......... 353 
(a) General statement ....... 353 
( b ) The egg. 354 
(c) The larva. 354 
(d) The pupa 355 
V. The Habits of the Female.356 
(a) Food and method of feeding ..... 356 
( b ) Preparation of food for the larvae .... 356 
(c) Oviposition.358 
VI. The Habits of the Male .. 359 
(a) General habits. 359 
(b) Courting. 359 
VII. The Numerical Proportion of the Sexes .... 360 
VIII. Fecundity . . 360 
IX. Longevity of the Female .... . 363 
X. The Unfertilized Female.363 
XI. Osmia rufa larvae and pupae used as hosts . . . 366 
XII. Winter rearing of Melittobia ...... 367 
XIII. Means of dispersal ........ 368 
XIV. Summary.368 
XV. Bibliography.369 
XVI. Explanation of Plate.370 
I. Introduction. 
(a) Material . 
Melittobia has attracted the attention of a number of entomologists since 
it was first described under the name of Cirrospilus acasta by Francis Walker 
in 1839 and a number of papers have been published contributing facts with 
regard to its life-history. 
Parasitology xrv 23 
