A BIOLOGY O F C R U S T A C E A 



36. C, Megalopa of a spider crab (Macropodia). 



antennae, known as a puerulus; this gradually assumes the adult 

 form. 



Further multiplication of names of larval stages has occurred in 

 the Stomatopoda. The stage at which hatching occurs is variable. 

 In some genera, such as Coronida, the egg gives rise to an antizoea, 

 which does not have stalked eyes in the first instar, and the 

 abdomen is not divided into segments. The abdominal segments 

 become progressively defined through several instars. In other 

 genera, such as Squilla, a pseudozoea hatches from the egg. This is 

 in some ways more advanced than the antizoea, and has the 

 abdomen divided into segments bearing rudimentary appendages, 

 but the appendages on the thorax are not so well developed. The 

 change to the adult form is gradual, without any abrupt transitions. 



In the accounts of the various larval forms and their succession 

 during the life history of the individual we have not related the 

 sequence to seasons or years. It would be impossible to generalise, 

 even for one small group. In the following pages some examples are 

 given of types of seasonal reproductive cycles and an attempt is 



