2. ATnERINICHTHVS. 405 



total length, aud nearly equal to the length of the head. The dia- 

 meter of the e}'e is one-fourth of the latter, two-thirds of the length 

 ~ of the snout, and ratlier more than one-half of the width of the in- 

 terorbital space ; in young individiials it is much larger, equal to the 

 ■width of the space between the orbits. The silvery streak occupies 

 the adjoining halves of tlie third and fourth series of scales. The 

 lower caudal lobe is longer than the upper. 

 Coasts of Brazil and Mexico. 



a. Fine specimen. Rio Janeiro. Presented by A. Fry, Esq. 



b. Fine specimen. Mexico. From M. SaUe's Collection. 

 e. Half-grown. 



9. Atherinichthys incisa. 



Atherina incisa, Jenyns, Zool. Beagle, Fishes, p. 79. pi. 16. fig. 2. 

 1^-5-6 1 8-^. A.j^3. L.transv. 12. 



The spinous dorsal fin is opposite to the space between the extre- 

 mity of the ventral and the oiigin of the anal. Each scale with one 

 or two dee}) incisions posteriorly. The height of the body is one-ninth 

 of the total length, the length of the head one-sixth. (Jen.) 



39° S. lat., 61° W. long. 



10. Atherinichthys argentinensis. 



Atherina argentinensis, Cuv. ^ Val. x. p. 350; Jenyns, Zool. Beugle, 

 Fkhes, p. 77. 



D. 5 j g^. A. ^. L. transv. 10. 



The anterior dorsal fin is opposite to the vent. Depth of the body 

 exactly one-ninth of the total length, measuring this last to tlie end 

 of the middle caudal rays ; the length of the head is five and a half 

 times in the same, measuring this last to the end of the caudal lobes. 

 Scales truncated behind, ■n'ith a single small notch on the middle of 

 the margin. Pectorals exactly the length of the head. Breadth of 

 the silverj' band one-fifth of the greatest depth of the body. {Jen.) 



Montevideo. Maldonado. 



11. Atherinichthys gracilis. 



D. 4 ||. A. ~. L. lat. 40. L. transv. 9. 



The origin of the anterior dorsal fin is opposite to the vent, exactly 

 in the middle of the distance between the end of the snout and the 

 base of the caudal. The distance between the origins of the two 

 dorsal fins is somewhat more than one-half of that between the origin 

 of the posterior and the caudal. The height of the body is contained 

 nine times in the total length, the length of the head five times and 

 a half. The silvery band is narrow, and occupies a portion of the 

 fourth series of scales. Scales with the margin entire. Caudal lobes 

 equal in length; caudal somewhat longer than the pectoral, and rather 

 shorter than the head. 



Hah. ? 



Thirty-one lines long. Probably young. 



