MIMICRY. 357 



No specialist who works long at any large group of animal 

 forms, especially at insects, can escape meeting with these pro- 

 blems. This is particularly discovered when, in monographing a 

 family, species are found resembling insects belonging to another 

 order. Thus, in recently working out some Hemiptera for the 

 1 Biologia Centrali-Americana,' I found in the family Lygceidce 

 a species with all the superficial form and colour of an Earwig 

 (Forficula) belonging to the order Orthoptera ; while among the 

 Lygceidce and Capsidce were many species which mimicked Ants 

 (Hymenoptera). To add to the problem, Lygceidce and Capsidce 

 were found mimicking one another. Dr. Thorell made a similar 

 observation in monographing Burmese Spiders. Ligdus chelifer 

 " is a small flat Spider belonging to the family Salticoidce, and 

 resembles very much a Cheloneth (Pseudoscorpion) ; Prolochus 

 longiceps has some resemblance to an Orbitelarian Spider of the 

 genus Meta (M. segmentata, f. inst.)."* Now, in the first case, and, 

 alluding to the writer's own experience, it appears we have " Sug- 

 gested or Probable Mimicry," because we possess no knowledge 

 whether these Hemiptera are found with the Earwigs and Ants 

 they mimic, nor whether they are avoided or neglected by enemies 

 because of this mimicry. We can only report that these insects 

 are mimics one of another as seen in our cabinets, and that as 

 nothing is, or can be, predicated as purposeless in nature, neither 

 can these assimilative forms be meaningless ; and, further, arguing 

 from demonstrated knowledge in other cases of mimicry being 

 protective, the presumptive evidence is that the theory of protec- 

 tion affords the clue to the origin of the mimetic guise of these 

 insects. But this is only circumstantial evidence of the weakest 

 description, and, though we may believe as a matter of biological 

 faith, based on analogous cases in nature, that this is the ex- 

 planation, it is probable, or more than probable, that the progress 

 of science is retarded by confounding scientific suggestion with 



at least five Bees are provided for each larva, the havoc caused in hives 

 where these insects abound must be considerable " (ibid. p. 36). The Horse 

 Bot Fly (GastropJiilus equi) also resembles the Honey Bee in size, colour, 

 and form, but protective mimicry here seems an altogether unwarranted 

 assumption, as the larval fly is parasitic in the alimentary canal of the 

 Horse. 



* ' Descrip. Catalogue Spiders of Burma,' Introtl. p. xiii. 



