The Bioiwiiiics of t^oiUlc African Insects. 369 



white patch on the costal border of the under-side of one 

 hind-wing, wrajiping round the front of the costa of 

 the fore-wing, meets the corresponding patch on the oppo- 

 site side, and is distinctly seen from tlie front. The speci- 

 men captured by Mr. A. H. Hamm, represented in the 

 adjacent Fig. 38, was probably seized soon after it had 

 alighted, wlien the wings were held in the manner indicated 

 in the figure, and before they were lowered between the 

 hind-wings in the attitude of repose. Or it is possible 

 that this specimen was seized duiing flight at the moment 

 when the wings came together. 



The theory of probability prevents the interpretation of 

 any but very rare symmetrical notches, except on the 

 supposition that the wings were together at the time of 

 the injury, and when the condition of the specimen is 

 fresh and the notch possesses a definite and similar shape, 

 fitting that upon the opposite side, there can be no hesita- 

 tion in inferring the attack of an enemy. 



Turning to unilateral injuries, of which many examples 

 will be found in Plates IX, X, and XT, Mr. Marshall is of 

 opinion that they are the strongest evidence of the attacks 

 of birds because they were almost certainly inflicted while 

 the insect was upon the wing. Perfectly fresh specimens 

 with such injuries of a very pronounced type are shown on 

 Plate IX, figs. 15, 19, and 23; Plate X, figs. 1, 3, 5, 19, 25. 

 29, etc. ; Plate XI, figs. 4, 6, 7, 11, etc. It is true that a 

 butterfly settled upon a flower with outspread wings 

 might be seized by one side ; but insects in that position 

 are on the alert, and many butterflies when slightly dis- 

 turbed will shut their wings with a snap when they do 

 not take flight. 



Looking at the injuries as a whole it is seen that the 

 great majority are inflicted at the anal angle and adjacent 

 hind margin of the hind-wing, a considerable number at or 

 near the apical angle of the fore-wing, and comparatively 

 few between these points, at or near the inner angles of 

 the wings. I was at first greatly struck by the compara- 

 tive rarity of injuries in the last position, but in a later 

 consignment Mr. Marshall forwarded many excellent 

 examples, referred to in the following paragraph : — 



''Salisbury, Sept. 27, 1901. — It was curious that just 

 after getting a letter from you, pointing out the greater 

 rarity of mutilation at the inner angles, I came across quite 

 a succession of excellent examples of this form. The 



TRANS. ENT. SOC. LOND. 1902. — PART III. (NOV.) 25 



