( cxciii ) 



who has had frequent opportunities of collecting and observing 

 Aculeates in many parts of the Palaearctic region, and has 

 noticed what kind of localities particularly coloured species 

 haunt, and to what extent similarly coloured species in differ- 

 ent groups occur in company with one another and with 

 similarly coloured forms belonging to other Orders, will feel 

 sure as I do — that in some way or other most of their colours 

 are Protective — Cryptic or Ajiosematic as the case may be, and 

 sometimes, perhaps, Cryptic in some surroundings and Apose- 

 matic in others (for it depends entirely on the surroundings 

 whether strongly contrasted markings catch the eye or confuse 

 it — attract attention or cZistract it.*) This applies evidently to 

 the two very common types of Aculeate coloration black-and- 

 yellow {]Vas2>Uke) and black-and-red (SphecoJes-like). These, 

 as I can say from pei'sonal observation, occur frequently in 

 all sorts of localities, forming regular Mullerian associations.'\ 

 At the same time I am convinced that, in some surroundings, 

 these same markings are as certainly Cryptic as the stripes 

 and spots of the great Felidae, whose habits as well as their 

 colours (" si parva licet componere magnis ") are not very un- 

 like those of the predaceous Fossors. Before quitting this 

 point, which (though connected with my proper subject) must 

 not detain me too long, I should like to say that I think these 

 insects are not so much qualified for entering into Synapose- 

 inatic groups by the fact that the $ possesses a sting, as by 

 some nauseous taste or smell (perhaps connected with Formic 

 acid ?) which both sexes possess. As Professor Poulton has 

 shown, stingless (^(^ do sometimes not only enter into, but form 

 centres of, such groups. And in this connection I may men- 

 tion Mr. Sladen's interesting observations, that (1) when a 

 male Humble Bee is caught in the fingers, its usual pleasant 

 fragrance is "now blended with an odour like that of sting- 



* It is difficult to doubt that the nauseous black-and-yellow larvae of 

 the Ciunabar moth are protected by Synaposematism (cf. foul ton, Colours 

 of Animals, p. 170). Yet I have often collected Aculeates on flowers of 

 Ragwort without noticing at first that the leaves of the same plants were 

 literally swarming with these gaudy caterpillars. Again, a Sawfly with 

 wasp-like colours, e. g. Strongylogaster cingulatus ? is certainly less con- 

 spicuous when resting on bracken than an all-black one like Selandria 

 morio (cf. Poulton, I. c, pp. 25-26). 



t Cf. Poulton in Trans. Ent. Soc, 1904, p. 645 etc. Cf. also Proc. 

 Ent. Soc, 1909, p. Ixix. 



N 2 



