908 



MIMICRY 



MIMULUS 



very characteristic ap|>earance, each homeward- 

 iNiu'nd ant carrying u piece of lent vertically in its 



J'aws. Schiter fniinil a hoinoptcrou- in-cci which 

 nitlifully resembled an ant together with its piece 



of leaf. The hitn-r was suggested hv tin- tliin c 



pressed green IMI.IV of tin- insect, and its profile was 

 precisely like thai of the jagged edge of the frag- 

 ment at leaf held over the wicE of the ant. 



The mimicking may IK; separated from the 

 iiiimicki-d -pecies liy a still wiiler interval. Spiders 

 in many parts of tin- world are defended by resem- 

 bling the aggressive and justly respected ants. 

 Again, many Ufgt caterpillars intimidate (heir foes 

 by resemblance to snakes. The extraordinary pre- 

 valence of mimicry among insects is prohalily to be 

 explained by their usual defenceless condition, and 

 by their immense fertility and the rate at which 

 the generations succeed each other conditions 

 which strongly favour the rapid action of natural 

 selection. Hence it is that other forms of protective 

 resemblance are also especially characteristic of 

 insects (see articles BUTTOTLY and CATERPILLAR 



in this work). Mimicry i>. however, by no means 

 unknown in other animal.-. Thus, the gaudy 

 colour* of the deadly coral snake- i Klaps \ of tropical 

 America are mimicked by haimlc-s snakes: and 

 the powerful friar- birds are resembled by deft 

 less orioles in various Malayan islands." All the 

 instances cited above illustrate protective mimicry 

 a resemblance which serves to defend the imitator 

 from attack. Hut there are other although far rarer 

 examples of aggres-ivc mimicry, in which the resem- 

 blance favours tin- attack of the imitator upon the 

 mimicked species or upon species which accompany 

 the latter. Thus, the larva- of certain Mies ( \ olu- 

 cella) feed upon the larva' of humble-hccs and 

 W.-I-IIH. The parent II y resembles the humble-liee 

 or wasp, and is thus less likely to arouse suspicion 

 when engaged in laying its eggs in or near the 

 nest. 



Mimetic appearances are often combined with 

 other methods of defence ; thus, many large cater- 

 pillars are well concealed by protective resemblance, 

 and only assume the terrifying snake like appearance 



when alarmed. It i of great interest to trace 

 the relation of niimicrv to the other uses of colour 

 in animals. This relationship is shown in the 

 alnive table. The dill'ereiice between mimicry and 

 protective resemblance (with which it is often con- 

 In-i'il i will lie seen when A is compared with 1!. 



The term mimicry has l>ccii criticised as seeming 

 to imply conscious volition on the part of the imita- 

 tor. Such a misapprehension is unlikely to arise in 

 any one who has read the literature of the subject. 

 Authorities are agreed thai the resemblance hax 

 Wii gradually produced by the operation of natural 

 selection which has en>urcd the persistence of all 

 variations tending in the direction of gome well- 

 defended insect avoided by foes. 



See H. W. Bate*, ' Butterflies of the Amazon ' ( Tran*. 

 Linn. NT*-., xxiii.); A. K. Waliao , ' Malayan Butterflies' 

 (Tmnt. /-mil, Sor., xxv.), Knsiiiin on Xnlm-nl N.'-rd'on, 

 Tropical A : K. Triincn, 'Smtli African 



Hultei-flic*' ( Tran* /.inn. .Vx-., xxvi.): Ilelt, ' Naturalut 

 In Nicaragua;' I'miltmi. '('..Imirs ami M.Tikinpiof Insvcts' 

 (/'roc. ZooL. Hoc., 1887), t.'oloun of Animal* (Inter. Sc. 



>lilllOSetr. a sub-order of I,eguminoo.T. disiin- 

 v'nished by regular Mowers and petals valviite in 

 bud. Over 1500 Htwries are known, all natives of 

 warm climates, a few only extending beyond sub. 

 tropical regions in the southern hemisphere. The 



and Mimosa are 



best 



genera Acacia (q.v.) 

 known. To the latter 

 genus belong the 

 Sensitive Plants 

 (<|.v. ), also a great 

 variety of trees 

 usually of lieautiful 

 foliage ( though their 

 leaves, as in Acacias, 

 may be reduced to 

 phyllodia) and often 

 also of valuable 

 timber. The fruits 

 are often esteemed, 

 but the roots and 

 seeds not unfre- 

 i|uciit.]y possess dras- 

 tic or even poisonous 

 properties. They are 

 also rich in tannin 

 and gums. 



Mini ultis. a 



genus of plants of the 

 natural order Scro- 

 phulariacen', having 

 a prismatic S-toothed 

 calyx, a somewhat bell-shaped corolla, of which the 



Mimulu* maculosns var. 

 Arlequin. 



