ISOPODA 



399 



Th.Q 



Fig. 276. A, Asellus aquaticus. Male viewed from above. From Leuckart 

 and Nitsche. an.' antennule; an." antenna; ah. 6, the last pair of abdominal 

 limbs ; t. testes with their efferent canals : the nervous system is shown in 

 black ; Th. z-Th. 8, thoracic limbs. B, Aega psora. B', Maxillule of the same. 

 All after Sars. 



