442 



CETJSTACEA. 



a H 



FIG. 351. a Lntcr'Nauplius larva. A, arms ; 07, proboscis with 

 mouth ; H, frontal horns ; D, intestine ; A', A", 1st and 2nd 

 antenna;; Mdf, mandibular foot (third pair of appendages). 

 I, Metanauplius larva of Salanns befoie the moult. Beneath 

 the skin are the rudiments of the lateral eyes (0) and all the 

 appendages F 1 to -F 1 " of the Cypris stage ; Ff, frontal filament ; 

 ff, unpaired eye ; Dr, gland cells of the anterior horns ; A*~, 

 the antenna? with suctorial disc ; MX rudiment of maxilla.-"" 



Krohn, open on a 

 prominence on the 

 basal joint of the 

 anterior pair of 

 thoracic appen- 

 dages. The eggs 

 accumulate in the 

 cavity between the 

 mantle and the 

 body in large 

 thin - walled flat- 

 tened sacs, which, 

 in the Lepadidce. 

 are attached to a 

 fold of the mantle 

 and are packed to- 

 gether on the dor- 

 fcal surface of the 

 animal. 



In spite of the 

 hermaphrodit i s m, 

 there are, accord- 

 ing to Darwin, in 

 certain genera 

 (Ibla, Scalpdlum) 

 very simply orga- 

 nised dwarfed 

 males of peculiar 

 form, the so-called 

 comp I em ent al 

 males, which are 

 attached like para- 

 sites to the body 

 of the hermaphro- 

 dite. There are 

 also dioecious Cir- 

 ripedes with a 

 strongly marked 

 dimorphism of the 

 sexes. This is the 

 case with Scalpel- 



