1064 



CRUSTACEA. 



scarcely longer than broad. The animal carried, below, a bag con- 

 taining six eggs. 



Calanus placidus. 



Frons rotundatus. Cephalothorax posticd obtusus. Antennae anticce 

 corporis longitudine, duplo leviter curvatce, apicibus fronte paulo poste- 

 rioribus; setis apicalibus brevibus, posticis penultimd antepenultimdque 

 valde elongatis, anticd penultimd dimidio breviore. Styli caudales 

 breves. 



Front rounded. Cephalothorax obtuse behind. Anterior antennaB as 

 long as body, slightly doubly curved, tips a little behind line of 

 beak, apical setae short, posterior penult and antepenult long, equal- 

 ling last five or six joints of antenna, anterior penult half as long, 

 apical and anterior antepenult short. Caudal stylets short, spar- 

 ingly longer than broad. 



Plate 73, fig. 4, animal, enlarged. 



Collected abundantly near the Kingsmill Group, April 30, 1841; 

 also, again in latitude 40° north, longitude 157° west, July 2, 1841. 



Length, one-twelfth of an inch. Colourless, or a little purplish. 

 Body moderately stout. Length of stylets not exceeding twice the 

 breadth. Setse of anterior antennae mostly about twice as long as 

 diameter of joints, much crowded towards base. First joint of the 

 anterior antenna short; second oblong; last three nearly equal. 

 Length of anterior seta of antepenult joint about equal to two 

 diameters of joint. Second pair of antennae rather short, with short 

 setae. Abdomen in specimen three-jointed. 



Calanus eecticornis. 



Frons obtusus. Cephalothorax postich rotundatus. Antennae antics cor- 

 pore longiores, rectissimce, apicibus fronte non anteriores, articulo 

 primo {2do ?) crassd oblongo, idtimopaulum demisso; setis brevibus, seta 



