reproduction of the Legs in Crahs and Spiders. 285 



cessarily but few books of reference of his ovvn to have recourse to, and 

 that it has been my lot to spend several years in a land luxuriant in the 

 gifts of nature, but barren in the works of art — a land far richer in vine- 

 yards than in museums, or libraries, or scientific institutions. 



I am, Sir, 



Your obedient humble servant, 



C. Heineken, M.D. 

 Funchal, Madeira, August 2, 1828. 



In one of the Edinburgh Journals of Science was published, some time 

 ago, (I think as long as two or three years,) a paper by Dr. M'CuUoch, 

 giving a minute and most interesting account of a peculiar suture, and a 

 muscular apparatus belonging to it, by which Crabs were enabled to 

 throw off their limbs, as occasion might require, at that particular part, 

 and that alone. He also, if I am correct, (for I quote from very imper- 

 fect notes, made at the time, and have not the number to refer to,) stated 

 that reproduction invariably took place from this part ; that they had not 

 the power of reproducing an extreme joint ; and that wlien such is muti- 

 lated the limb will always be parted with at the suture. Upon several of 

 a species of Grapsus ? abundant here, but new to me, I tried the follow- 

 ing experiments. It is necessary to remark, that in these, and also in 

 those on Spiders, I have used the terms first, second, and extreme joints, 

 instead of femur, tibia, and tarsus, as being more general and less tech- 

 nical. 



L 



Threw off two legs at the suture, upon the extreme joint being con- 

 fined. 



2. 



Threw off three under similar circumstances. 



3. 

 Threw off two at the instant their second joints were being divided by 

 a strong sharp pair of large scissors. The division was somewhat 

 tardy. 



4. 



The same. — The division with the scissors was momentary. 

 Vol. IV. u 



