Some observations on the internal morphology of Hansen's nauplius Y (Crustacea)
The internal morphology of the crustacean larval form that Hansen (1899) called nauplius y has revealed a remarkably advanced early nauplius. The nervous system is well developed and differentiated. It is connected with the anlagen of the compound eyes. A presumed filamentous base of the SPX-organ connects with these. The nauplius eye is present in a three-partite form with two retinula cells in e