PROTECTIVE RESEMBLANCE 181 



esrgs of these insects bear a close structural resemblance 

 to the seeds of plants. 



All other Phasmids are endowed with a wonderful 

 resemblance to twigs or steins. When wings are present, 

 they fold up so tightly as to be scarcely noticeable when 

 the insect is at rest ; but many of the species fail to 

 develop wings even in the adult state. The body and 

 legs are nearly always ludicrously long and slender, while 

 in some cases the effect is heightened by the presence of 

 moss-like outgrowths, or strong spines, which have the 

 appearance of thorns. When the sexes differ, the female 

 is always more plant-like than her mate. Four or five 

 species of stick insects, belonging to the genus Bacillus, 

 are found in southern Europe, and one of these has been 

 extensively reared in captivity in England during recent 

 years. The temperature of an ordinary living room agrees 

 admirably with these interesting " pets," which feed readily 

 upon privet, and lay an abundance of eggs from which 

 young hatch in due course. The manner in which these 

 creatures pose among the twigs of their food-plant is an 

 interesting object lesson in special protective resemblance, 

 and enables the stay-at-home naturalist to appreciate the 

 descriptions of those who have seen Phasmids in the 

 tropics. The following word-picture by the late Professor 

 Drummond has reference to a Central African species 

 called by the natives " Chirombo." " Take two inches 

 of dried yellow grass stalk, such as one might pluck to 

 run through the stem of a pipe ; then take six other pieces 

 nearly as long and a quarter as thick ; bend each in the 

 middle at any angle you like, stick them in three opposite 

 pairs, and again at any angle you like, upon the first grass 

 stalk, and you have my « Chirombo.' When you catch 

 him, his limbs are twisted at every angle, as if the whole 

 were made of one long stalk of delicate grass, hinged in 



