INLAND FISHERIES. 69 



XVI. Is the popular Idea that tJie dhmeinheved fragiaents of a, 

 starfish xoill i^egeiierate new starfish founded on fact ? 



This idea is commonly held, and is apparently founded on the 

 fact that in nearly every lot of stars brought up in the dredges or 

 on the mops a considerable percentage of stars may be found 

 which are regenerating lost parts. Frequently two, three, or even 

 four arms are being regenerated, and these are much smaller than 

 the original arms. Upon careful examination and inquiry into the 

 extent of this regeneration, I have never found a well authen- 

 ticated case among our species of stars in which part of the disc 

 was being regenerated, except those reared with great care in the 

 aquarium. With this point in view, I have examined a large 

 number of regenerating stars caught in their natural haunts, some 

 of them reported to be regenerating part of the disc, but invariably 

 the regeneration was limited to the arm. I have, however, made 

 a few experiments in the aquarium and in the cars, which have a 

 bearing upon this question of regeneration. 



The fact that a mutilated arm is frequently loosened and dropped 

 off at a particular point near the base, and the rate of regeneration 

 of specimens which have thus lost one or two arms, are recorded in 

 a previous chapter, page 63. 



All the arms may be pulled off, and, if the star is protected and 

 fed, all will generate. Such a specimen is sketched in Fig. 25. 

 This specimen was kept, after the operation, in a glass dish with 

 frequent changes of water, and was fed upon the soft parts of 

 crabs, etc. The regeneration was slow as compared with that 

 given in the previous tables, the new growth shown in the figure 

 (which is natural size) requiring about five or six weeks, probably 

 owing to the comparatively small amount of food taken. 



Since a mutilated arm drops off from the disc so readily, the 

 latter nearly always remains intact, and in ordinary cases, there- 

 fore, if two stars were to result from one, one of them must re- 

 generate from a single arm. I have several times kept single arms 

 for a long time in the aquarium or cars, but have never seen any 



