Notes on the Natural History of the Scorpion. 393 



days brought forth their young in confinement, and permitted 

 them to live, he saw them, each and all, change from a milk- 

 white color to a rusty brown. He saw them fix themselves 

 on the back and belly of the mother. They lived a fortnight 

 together quietly and well, but after this they daily died. He 

 does not say they disappeared. At the end of a month there 

 were only two living young ones. 



We want a variety of precise facts. We have ordinarily 

 only casual occurrences noticed. We should have the patient 

 investigations of months, and, if possible, of a whole year. 



Note. — I submitted the foregoing paper to my friend 

 Mr. Henry Krebs, of the Island of St. Thomas, W. I., a careful 

 observer, who favored me with the following remarks. (T. B.) 



1. The young of the scorpion are born at intervals. As seen 

 on the mother's back they are of different sizes, which proves 

 that they are not born simultaneously. The largest (oldest) 

 ones are nearest to the head, and the smallest (youngest) to the 

 tail of the mother. 



2. The young change their integument at least once while 

 living on the back of the mother, where I have repeatedly seen 

 the " epidermal sheath" of the young. 



3. It is very probable that the young leave the back of the 

 mother as soon as they have for the first time changed their 

 integument; at least I have found them, of the size they have 

 attained at that period, living apart from her. 



4. That the young kill and eat the mother is, I think, very 

 doubtful. In my opinion they leave her back when she catches 

 her prey and partake of it with her, after which they resume 

 their place. 



5. The West Indian scorpion leaves the wings, but devours 

 the legs of the cockroach. 



