266 



LEON J. COLE. 



Addendum. 



Since it is of advantage to place on record where they may be 

 found the cases of abnormal crustacean appendages, it may be 

 well to call attention here to two recent records which might 

 naturally be overlooked. They both occur on crabs, and both 

 belong to the class of "extra processes arising from the normal 

 dactyl," being directly comparable to the chelae figured by Emmel 

 (1907, pi. I, Fig. i), Faxon (1881, pi. i. Figs, i, 2, 3, 4, 5, 7, 8), 

 Herrick (1895, pi. 47, Fig. 191), and Bateson (1894, Figs. 184, 

 185). 



The first case is fiured incidentally by Verrill (1908, p. 396, 

 Fig. 37) in his report on the "Decapod Crustacea of Bermuda." 



Fig. 8. Deformed claw of an undetermined cancroid crab. (After Verrill.) 



Fig. 8 represents the condition of this specimen, which is de- 

 scribed as the "deformed claw of an undeterminal cancroid crab." 



Fig. 9. Abnormal crab claw from Stonington, Conn. (After Leavitt.) 



The second case (Leavitt, 1909), illustrated in Fig. 9, is of a 

 crab, possibly Callinectes, from Stonington, Conn. The author 

 states that there was a brief mention of this claw in St. Nicholas 

 for December, 1907. He makes the mistake of considering this 

 a reduplication of the entire claw, except that "in the small 

 pincer the dactyl is not movable at the base, as it is in the larger 



