REPORT OF COMMISSIONERS OF INLAND FISHERIES, 133 



Kenntni's erheilt, wird wohl in der Reich der Fischermythen zu 

 verweisen sein" (p. 333).* 



Apparently it was not until the year 1906 that any authentic 

 account was given of a lobster with two crushing chelae. During this 

 year two such lobsters were recorded; one of these was specimen 

 No. 8 of the present article, which was obtained in 1905 (see Emmel, 

 '06) ; the other was reported for a European lobster by Dr. W. T. 

 Colman, in the Proceedings of the Zoological Society of London for 

 1906. On page 633 of that journal is "exhibited the photograph of 

 a lobster (Homarus grammarus, Linn.) with symmetrically developed 

 chelae [i. e., two crushers], recently presented to the Natural History 

 Museum by the Directors of Harrod's Stores, Ltd." (p. 634). 

 Finally, lobster No. 9 of this report adds a third specimen to the 

 list. We have now on record, therefore, at least three authentic 

 cases of lobsters with similar crushing claws. 



2. The Theoretical Significance of these Abnormal Structures. 

 A. Limhs ivith Paired Extra Processes. 

 1. Bateson's Principles for Secondary Symmetry. 



Bateson, in his masterly work on variation, has been able to formu- 

 late certain relations or principles to which a great majority of 

 variations seem to conform. These relations are all the more strik- 

 ing because they enable one even to predict with a considerable degree 

 of accuracy what certain characteristics of a given abnormality will 

 be! A brief statement of certain of these principles which refer 

 especially to Crustacea seems necessary here before discussing the 

 theoretical aspect of the present cases. 



There are at least three possible categories for crustacean limbs 



*I must hasten to add here, however, that this opinion of Przibram's in regard to the mytho- 

 logical character of Herrick's lobster does not represent his later conclusion. In a previous 

 article I (Emmel, '06) unfortunately overlooked Przibram's latest conclusion on this matter 

 in his recent work on "Die Heterocheb'e bei decapoden Crustaceen," 1905. And, in a recent 

 letter, he has kindly called my attention to the fact that in this monograph he has withdrawn 

 his earlier opinion as to the mythological character of said lobster. I therefore gladly take 

 this first opportunity to correct my previous oversight. 



