EITHAUSIA RECURVA. 233 



enumerated above proves that E. cximia must be extremely common in the ma- 

 jor part of the area of the East Pacific investigated by Dr. Agassiz in 1904-1905, 

 but yet not found South of Lat. 14?° S., in the whole southwestern part South of 

 the line, towards Manga Reva, nor in the inner part of the Gulf of Panama; 

 and not a specimen has been taken near the Fiji Islands, nor, so far as I know 

 at present, in the tropical West Pacific. — The list shows that the species was 

 rather frequently taken at the surface. 



1.3. Euphausia recurva H .J. Hansen. 



Plate 7, fi5,'s. 3a-3n. 



1905. Euphausia rccurm H. J. Hansen, Bull. Mus. Ocean. Monaco, no. 42, p. 1,3. 



Sta. 4576. Oct. S, 1904. Lat. 29° .52' N., long. 116° .jO' \V. Surface. 24 a", 1 cf juv., 1 9 . 



Description. — The frontal plate (fig. 3a) very short and shaped as in E. 

 eximia; the rostrum is very acute, shaped as a rather narrow or very narrow 

 triangle, from a little to considerably longer than the breadth of second antennu- 

 lar joint : the keel from the basal part of the rostrum to the posterior end of the 

 oblong dorsal area nearly as in E. exi/nia. 



The eyes are medium sized, a little smaller than in E. eximia. — The anten- 

 nular peduncles show interesting features. The basal joint is slightly more than 

 twice as long as broad, as long as the sum of the two other joints, and the upper 

 distal lobe differs extremely in the two sexes. In the male (figs. 3b and 3c) 

 it is a very oljiong-triangular plate much longer than broad, longitudinally some- 

 what curved so that it is less or more hollowed, at the base from a little less to a 

 little more than half as broad as the entl of the joint, at the end acute or even 

 acuminate, cUrected upwards and somewhat backwards. In the female the 

 lobe is vertical or a little recurved (figs. 3d and 3e), somewhat more than half 

 as broad as the end of the joint, with the lateral margins subparallel, while the 

 distal margin is deeply and more or less oblitiuelj' concave; the distal part of 

 the lobe is therefore shaped as two triangular, acute processes either nearly 

 equal in length or the inner somewhat or much longer than the outer, which 

 sometimes is short. The two distal antennular joints are thicker in the male 

 than in the female. Second joint increases somewhat in iweadth from the base 

 to considerably lieyond the middle; its terminal upper margin is somewhat 

 oblique; a littl(> inside and behind the distal outer angle a thick, angular pro- 

 tuberance or short, obliquely conical tubercle is seen, while a little inside and 

 beliind the cUstal inner angle a slender, spiniform, acute process projects forwards 



