LIGIA OCEANICA. 



447 



The male organs consist of a pair of small styliform 

 processes, centrally attached to the anterior or first seg- 

 ment of the pleon. These are connected by slender 

 ductus ejaculatorii to a vas deferens, that suddenly enlarges 

 and gradually diminishes to the extremity, where it 

 divides into three testes, which enlarge, and gradually 

 thin out with extreme delicacy. The external surface 

 of the ductus ejaculatorii is marked by many small cells 

 of black pigment. 



This species is connnon on all our coasts, running 

 with agility, and folding in the extremities so as to feign 

 death. It indiscriminately feeds on decaying animal and 

 vegetable substances, along tide-marks and rocks. It is 

 seldom found under water, and may be observed running 

 over the sand in full sunshine. 



We have occasionally found them dead, yet standing 

 on the rock as if they were alive and well. On exa- 

 mination, we have found that the branchial plates had 

 been destroyed, probably by some insect, but of this 

 fact we have no direct evidence. 



Microscopical representation of the texture of tlie dorsal 

 tegument of Ligia oceanica. 



