284 Colour and the Struggle for Life 
naturalists in many lands; but nearly all of them known since that 
general awakening of interest in the subject which was inspired 
by the great hypotheses of H. W. Bates and Fritz Miiller. We find, 
however, that Burchell had more than once recorded the mimetic 
resemblance to ants. An extremely ant-like bug (the larva of a 
species of Alydus) in his Brazilian collection is labelled “1141,” with 
the date December 8, 1826, when Burchell was at the Rio das Pedras, 
Cubat&o, near Santos. In the note-book the record is as follows: 
“1141 Cimex. I collected this for a Formica.” 
Some of the chief mimics of ants are the active little hunting 
spiders belonging to the family Attidae. Examples have been 
brought forward during many recent years, especially by my friends 
Dr and Mrs Peckham, of Milwaukee, the great authorities on this 
group of Araneae. Here too we find an observation of the mimetic 
resemblance recorded by Burchell, and one which adds in the most 
interesting manner to our knowledge of the subject. A fragment, 
all that is now left, of an Attid spider, captured on June 30, 1828, 
at Goyaz, Brazil, bears the following note, in this case on the specimen 
and not in the note-book : “Black...runs and seems like an ant with 
large extended jaws.” My friend Mr R. I. Pocock, to whom I have 
submitted the specimen, tells me that it is not one of the group 
of species hitherto regarded as ant-like, and he adds, “It is most 
interesting that Burchell should have noticed the resemblance to an 
ant in its movements. This suggests that the perfect imitation in 
shape, as well as in movement, seen in many species was started in 
forms of an appropriate size and colour by the mimicry of movement 
alone.” Up to the present time Burchell is the only naturalist who 
has observed an example which still exhibits this ancestral stage in 
the evolution of mimetic likeness. 
Following the teachings of his day, Burchell was driven to believe 
that it was part of the fixed and inexorable scheme of things that 
these strange superficial resemblances existed. Thus, when he found 
other examples of Hemipterous mimics, including one (Ladéeva 
macrophthalma) with “exactly the manners of a Mantis,” he added 
the sentence, “In the genus Cimex (Linn.) are to be found the 
outward resemblances of insects of many other genera and orders” 
(February 15, 1829). Of another Brazilian bug, which is not to be 
found in his collection, and cannot therefore be precisely identified, 
he wrote: “Cimex...Nature seems to have intended it to imitate 
a Sphex, both in colour and the rapid palpitating and movement of 
the antennae” (November 15, 1826). At the same time it is im- 
possible not to feel the conviction that Burchell felt the advantage 
of a likeness to stinging insects and to aggressive ants, just as he 
recognised the benefits conferred on desert plants by spines and by 
