118 The Inheritance of Colour in Carausius morosus. 



browns : there is no evidence in favour of the view that an insect becomes 

 brown if reared in the shade. 



(9) In a general way the production of a small proportion of browns is 

 a help to the concealment of the animal under normal conditions, since such 

 specimens resemble dried twigs. 



(10) Males are produced from the eggs of unfertilised females, but are 

 extremely rare. 



In conclusion we should like to express our deep obligation to Prof. Lefroy 

 for his invaluable help, both in giving advice as to methods of rearing and in 

 devising apparatus. 



LIST OF WOBKS EEFEEEED TO IN THIS PAPEE. 



Meissner, O., " Biologische Beobachtungen an der indischen Stabheuschrecke (JMxippus- 

 morosus)," 'Zeit. fur wissensch. Insektenbiologie,' vol. 5, 1909. 



Schleip, W., " Die Farbenweehsel von Dixippus morosus (Phasmidae)," ' Zool. Jahrbiicher 

 (Abt. fur Syst.),' vol. 30, 1911. 



de Sinety, M. E., "Eecherches sur la biologie et l'anatomie des Phasnies," 'La Cellule,' 

 1901. 



Von Wattenwyl, K. B., and Eedtenbacher, J., ' Die Insektenfamilie der Phasmiden,' 

 Leipzig, 1908. 



EXPLANATION OF PLATES. 



Fig. 1. — Six specimens of adult female seen from the side, to illustrate some of the 

 variations in colour. Eeduced to two-thirds of the actual length. 



A. Light brown or hazel variety. 



B. Dark brown variety. 



C. Yellow variety. 



D. Eed brown variety. 



E. Pure green variety. 



F. Olive green variety. 

 Fig. 2— The adult male. 



A. From the side. 



B. From beneath, showing the rosy flush which indicates sexual maturity. 



Eeduced to two-thirds of the actual length. 

 Fig. 3. — The just-hatched insect emerging from the egg. Slightly enlarged. 

 Fig. 4. — The just-hatched insect. Enlarged five diameters. 



A. Seen from above. 



B. Seen from the side. 



Fig. 5. — Two insects in the second instar. Magnified two and a half diameters. 



A. An insect which has turned brown, seen from beneath. 



B. The same insect seen from above. 



C. An insect which has turned green, seen from beneath. 



D. The same insect seen from above. 



