150 REPORT OF COMMISSIONERS OF INLAND FISHERIES. 



have arisen through an accidental fracture of the nerve stump and 

 a consequent triple regeneration. 



In the conclusion of this study of abnormal structures, therefore, 

 we may say that sufficient evidence has now been adduced to prove 

 that both abnormal symmetrical and duplicated appendages among 

 curstacea do arise through the process of regeneration. And the 

 experimental results so far attained indicate that we may yet be 

 able to control the formation of these abnormalities by proper muti- 

 lation, and thus open up for experimental study an important field 

 of organic variation. 



Literature Cited. 



Andrews, E. A., '04 — "An Aberrant Limb in the Crayfish." Biol. 



Bull, Vol. VI, No. 2, pp. 75-83. 

 Bateson, W., '94 — " Materials for the Study of Variation." London,. 



1894. 

 Calman, W. T., '06 — "Exhibition of a Photograph of a Lobster 



with Abnormal Chelae." Proceed, of the Zool. Soc. of London,. 



p. 633. 

 Emmel, V. E., '05 — "The Regeneration of Lost Parts in the Lobster." 



Thirty-fifth Annual Report of the Rhode Island Commission of 



Inland Fisheries, pp. 81-117. Special paper. No. 20. 

 Emmel, V. E., '06 — "The Relation of Regeneration to the Molting 



Process of the Lobster." Thirty-sixth Annual Report of the 



Rhode Island Commission of Inland Fisheries, pp. 257-313; 



Special paper, No. 27. 

 Emmel, V. E., '06 — (a) "Torsion and Other Transitional Phenomena 



in the Regeneration of the Cheliped of the Lobster." Journal 



of Exp. Zoology, Vol. Ill, No. 4, pp.603-618. 

 Emmel, V. E., '06 — (b) "The Regeneration of Two 'Crusher-claws' 



following the Amputation of the Normal Asymmetrical Chelae 



of the Lobster {Homarus Americanus) ." Archiv. f. Entw- 



Mech., Bd. XXII, pp. 542-552. 



