178 [August, 



coustaiitly carried on a single card. The collectiou includes many 

 specimens captured and presented by Mr. Hamm's son, Mr. C. H. 

 Hamni. 



A part of the results has been already published in the ' Entomo- 

 logist's Monthly Magazine' for 1908, p. 181, and 1909, pp. 132 and 

 157 ; biit the most novel and interesting observations and conclusions 

 — those obtained with the genus Hilara are made known for the first 

 time in the following brief account of Mr. Hanun's gift. The full and 

 detailed account awaits publication until niunbers of obscure and 

 minute insects — Dipterous captors and prey chiefly Dipterous — have 

 been satisfactorily worked out. 



The collection has been classified by Mr. Hamm so as to illustrate 

 his conclusions, the species being arranged in groups, each repre- 

 senting a definite evolutionary stage in the use of prey — first and 

 lowest as food devoured by both sexes without relation to pairing, 

 then as a gift provided by the male and devoured by the female 

 during pairing, finally — as it were an ornament or plaything — -no longer 

 eaten by the female, but acting as a lure and a stimulus. In this last 

 stage the prey is often replaced by some vegetable fragment which is 

 quite unsuitable as food. The climax of this line of evolution is 

 reached in an elaborate cocoon spun by the male around the prey and 

 replacing the latter as an object of attraction. This replacement is 

 self-evident in many examples studied by Mr. Hanun ; for in these 

 there was nothing but an empty cocoon, the prey having probably 

 been lost during the process of construction. 



There are strong reasons for the belief that the last stage has 

 been reached through the second, and the second through the first, 

 but this inference must not be extended further and made to apply to 

 the species themselves. 



I.- — Prey devoured by both sexes independently of pairing. 



A. Tachydroviia (Tachydrominas). Pi'ey very nearly always Dipt- 

 erous and often belonging to the genus Tachydromia, perhaps sometimes 

 to the same species as the captor. The female in cojmJa has very rarely 

 been found with prey. 1908 — ninety catalogued specimens (or mounts) 

 of which 17 were captiu-ed by Mr. C. H. Hamm; 1909 — eighty-six of 

 which 2 were captured by Mr. C. H. Hamm ; 1911 — thirty. 



B. Hyhos (Hyhotinas). Prey generally Hymenopterous. 1908 — 

 eighty-four of which 26 were captured by Mr. C. H. Hamm ; 1909 — 

 two ; 1911 — six. 



