SHRIMPS, CRABS, AND BARNACLES 107 



ments caused by the strokes of the two front legs and of 

 the pair which will become the mandibles. Their limbs 

 have the special form and are beset with the feather-like 

 hairs, and the whole creature has the kite- like shape 

 characteristic of the nauplius young of other Crustacea. 

 They are indeed indistinguishable from those young. 

 Whilst it was the Army doctor, Vaughan Thompson, 

 who discovered that barnacles are strangely altered 

 " shrimps," it was Darwin who made one of the most 

 interesting discoveries about them a discovery of which 

 he was always, and rightly, very proud as I will explain 

 in the next chapter. 



