But, as far as structure is concerned, I can see no similarity between tridactyle pedicellariae and avicularia.

The latter resembles somewhat more closely the chelae or pincers of Crustaceans; and Mr.

Mivart might have adduced with equal appropriateness this resemblance as a special difficulty, or even their resemblance to the head and beak of a bird.

The avicularia are believed by Mr.