A Nebalia from Laguna Beach 



R. LA FOLLETTE 



Among the many marine forms collected and studied at Laguna 

 Beach this summer were several Nebalia, which were taken by Mr. 

 Lichti from a hold fast cast up on the beach. A specimen was 

 sent to the National Museum at Washington, where it was classified 

 as Nebalia bipes O. Fab. A brief description of the animal will 

 be given in this paper. 



Nebalia bipes O. Fab. (Plate I, Fig. 1) belongs to the order 

 Phyllocarida, which is the linking order between the Branchiopoda 

 and Copepoda on one hand and the Schizopoda and Decapoda on 

 the other. There are only three genera, and the commonest of 

 these is Nebalia. So far as I know this form has never before been 

 reported from this region. The specimen here described was 9 

 mm. in length and a whitish flesh color. It was transparent in the 

 living animal. The body is divided into a head, thorax and abdo- 

 men, having the normal malacostracan number of segments, except 

 the abdomen, which is made up of eight, the last bearing caudal 

 styles. There is a bivalved cephalic carapace extending back to 

 the fourth abdominal segment and terminating in front in a movable 

 rostrum. The eyes are large, round and raised on movable stalks. 



There are two pairs of antenna (Plate II, Fig. 2), the first 

 pair being four-jointed, the last joint rather broad and armed with 

 many hairs along the outer margin. The other joints have a few 

 hairs on the articulating margin. The flagellum rises from the 

 fourth joint, behind the fifth and has fourteen joints, each one 

 armed with several hairs on the outer margin of the articulation. 

 The second antenna are slightly larger than the first and made up 

 of three joints with a brush of plume hairs at the caudal end of the 

 second joint. The flagellum is fourteen jointed. The mandible 

 has a two-jointed palp (Fig. 3), with numerous hairs along the 

 outer margin. The second maxilla also has a palp extending back 

 under the carapace with the function of keeping the carapace free 

 from foreign bodies. 



