A REVIEW OF THE MYSIDACEA 245 



Remarks. — This species is readily recognized by the very acutely 

 pointed apex to the antennal scale. The telson is linguif orm in shape, 

 twice as long as broad at the base, without apical cleft, terminated 

 by a single pair of long spines, lateral margins with 30 to 31 short 

 spines extending along the entire margin from the base to the apex. 



MYSIDOPSIS INERMIS Coifmann 



Mysidopsis inermis Coifmann, 1937, p. 8, fig. 4. 



Distribution. — Known only from the original record from Guayas*. 



Remarks. — This species is closely related to M. calif ornica Tatter- 

 sall, but it differs in the following characters : ( 1 ) The elongate form 

 of the eye; (2) the absence of a distal joint to the antennal scale; (3) 

 the absence of spines on the inner uropod. 



METAMYSIDOPSIS PACIFICA (Zimmer) 

 Mysidopsis pacifica Zimmer, 1918, p. 19, figs. 16-24. — Coifmann, 1937, p. 11, fig. 6. 



Distribution. — Known only from Callao, Chile*. 



Remarks. — This species is very similar to M. elongata Holmes, from 

 which it may be distinguished by the following characters: (1) The 

 form of the telson, which has the apex much less convex and the 

 spines terminating the lateral margins more sharply marked than in 

 M. elongata. (2) The antennal peduncle, which is longer than the 

 first joint of the scale, whereas in M. elongata it is shorter. (3) Ab- 

 sence of the three separate distal spines on the inner margin of the 

 inner uropods. 



Coifmann examined numerous specimens of this species from Callao, 

 the type locality of the species, and finds that these differences are 

 constant. She considers the differences sufficient to justify the sep- 

 aration of 31. pacifica from elongata. 



PROMYSIS ATLANTICA Tattersall 



Figure 56 

 Promysis atlantica Tattersall, 1923, p. 286, pi. 1, figs. 5-6. 



Distribution. — The type and only known specimen was taken off Rio 

 de Janeiro. It has not again been recorded. 



Remarks. — This Atlantic representative of the genus is closely al- 

 lied to the type species, but it may be distinguished by the following 

 characters : 



(1) The eyes (fig. 56, a) are longer in proportion to their breadth 

 (2% : 1), and the cornea is only half as long as the stalk. In P. orien- 

 talis the eye is V/ 2 times as long as broad, and the cornea is only 

 slightly shorter than the stalk. 



