A REVIEW OF THE MYSIDACEA 195 



Distribution. — This species is known only from Japan. Nakazawa 

 states that it is abundant in brackish water and forms the object of 

 an important fishery at all times of the year. I have no information 

 of the type of locality in which the present material was collected. 



Remarks. — These specimens agree closely with the description and 

 figures given by Nakazawa (1910). The only reference to the species 

 subsequent to Nakazawa's paper is by Ii (1936a) who mentions 

 the species without further description except to say that he had 

 observed sternal processes on the seventh and eighth thoracic sterna 

 of the female and the baling lobe on the anterior oostegites. I have 

 myself failed to find the sternal processes in the females of this species. 



N. japonica may be recognized by the following characters: (1) 

 The carapace is produced into a rostral plate, which is broadly 

 rounded, almost semicircular in shape. (2) The eye is about twice 

 as long as broad, and the cornea occupies the distal third. (3) The 

 antennal scale (fig. 76, a) is 10 times as long as broad. (4) The sixth 

 joint of the endopod of the third to the eighth thoracic limbs is divided 

 into 8 to 12 subjoints. (5) The telson (fig. 76, c) is triangular in 

 shape, twice as long as broad at the base, lateral margins armed with 

 about 40 more or less uniform short spines, not arranged in series, 

 but regularly spaced ; apex armed with two pairs of spines, the outer 

 pair twice as long as the inner. (6) The fourth pleopods of the male 

 (fig. 76, b) have the proximal joint of the exopod nine times as long 

 as the distal joint and the terminal setae are three times as long as 

 the distal joint. 



I counted 30 embryos in the brood pouch of a large adult female. 



NEOMYSIS AMERICANA (&. I. Smith) 



Figure 77 



Mysis americana Smith, 1873, p. 552; 1S79, p. 106. — Vermis, 1874a, p. 45. 

 Mysis americanus Benedict, 1885, p. 176. — M. J. Rathbun, 1905, p. 27. — Paulmier, 



1905, p. 128.— Fowler, 1912, p. 541. 

 Neomysis americana Sumner, Osburn, and Cole, 1913, p. 663. — Fish, 1925, p. 



152.— Tattersall, 1926, p. 12; 1939b, p. 285.— Proctor, 1933, p. 243.— Fish 



and Johnson, 1937, pp. 285, 298. 



Occurrence. — East coast of North America: Portland Harbor, 

 Maine*, identified by Hansen; Vineyard Sound*, identified by S. I. 

 Smith ; Vineyard Sound, surface, evening, August 29, 1882, 1 breeding 

 female; Vineyard Sound, surface, January 21, 1876, V. N. Edwards 

 collector, 2 males, 2 females; Vineyard Sound, surface, January 12 

 to 14, 1880, V. N. Edwards collector, 1 male, 1 nearly adult female, 

 20 immature; U. S. Fish Commission locality 314, off Cape Cod, 6 

 fathoms, August 29, 1879, 5 specimens; numerous collections were 

 made at Woods Hole : No specific data, several hundred specimens ; 

 2 males, 1 female, identified by Verrill* ; surface, March 7, 1888, about 

 a hundred specimens ; surface, March 12, 1888, 4 males, 4 females, 4 



