140 HISTORY OF CRUSTACEA. CHAP. XII. 



minute; the palpi and exterior maxillae have almost 

 disappeared ; the cirri are thick, inarticulate, and desti- 

 tute of bristles ; and the muscles both of the mouth and 

 cirri are without transverse striation. Darwin found 

 the stomach perfectly empty in the animal examined 

 by him. 



Having reached the Nauplius, the extreme outpost of 

 the class, retiring furthest into the gray mist of primi- 

 tive time, we naturally look round us to see whether 

 ways may not be descried thence towards other border- 

 ing regions. By the structure of the abdomen in 

 Nauplius we might be reminded, like Oscar Schmidt, 

 of the moveable caudal fork of the Kotatoria, which 

 many regard as near allies of the Crustacea, or at any 

 rate of the Arthropoda; in the six feet surrounding 

 the mouth we might imagine an originally radiate 

 structure, and so forth. But I can see nothing certain. 

 Even towards the nearer provinces of the Myriopoda 

 and Arachnida I can find no bridge. For the Insecta 

 alone, the development of the Malacostraca may per- 

 haps present a point of union. Like many Zoeae, the 

 Insecta possess three pairs of limbs serving for the 

 reception of nourishment, and three pairs serving for 

 locomotion ; like the Zoea3 they have an abdomen with- 

 out appendages ; as in all Zoese the mandibles in 

 Insects are destitute of palpi. Certainly but little in 

 common, compared with the much which distinguishes 

 these two animal-forms. Nevertheless the supposition 

 that the Insecta had for their common ancestor a Zoea 



