123 



sixth abdominal segment as long as the two preceding; the caudal 

 segment longer than the lamelloe; the two subapical barbs salient. 



The tumid, hunched appearance of the anterior portion of the cara- 

 pace, and the spines at the apices of the first and second basal joints of 

 the inner antennae, are characters which have not been mentioned in 

 any previously-described species of this genus. They are very charac- 

 teristic of this species, and will serve readily to distinguish it from all 

 others. 



Length, .45 of an inch. 



Locality : North Pacific Ocean. Latitude 30<^ north ; longitude 145° 

 west. Caught June 28, 1873. 



CYETOPIA EOSTRATA, JDana. 



Cyriopia rostraia, Dana, U. S. Expl. Exped. Crust., i, 648, pi. 43, f. 2. 



Locality : ]!^orth Pacific Ocean. Latitude, 3° north ; longitude, 128° 

 west. Collected May 10, 1873. 



Several specimens of this species were obtained, and they are all 

 more rudimentary in form than that described bj^ Dana. I failed to. 

 detect the slightest evidence of brancbite. These organs were rudi- 

 mentary in Dana's specimen ; and in another genus — Furcilia, which is 

 very closely allied, and more rudimentary still — they are entirely absent. 

 In one instance tbe carapace was excavated behind, across the dorsum, as 

 in tbe latter genus. All the specimens, but one, showed the apex of the 

 first joint of the inner pair of antenncs prolonged at its outer and inner 

 angle beyond the summit of the following joint, to about the same 

 extent as it is carried in some species of Furcilia. The abdominal feet 

 were rudimentary. The gibbous eyes, the long acute beak, and the 

 anteriorly projecting tooth on the lateral border of the carai^ace were 

 present in all. The facts cited above add greater weight to the testi- 

 mony already adduced, that the place for Dana's provisional genus 

 Furcilia is near Cyrto2)ia, in the family Fuphatisidce. 



MYSID^. 

 MYSIN^. 



SIRIELLA GRACILIS, Dana. 

 Sirielln gracilis, Dana, U. S. Expl. Exped. Crust., i, 658, pi. 44, f. 1. 



Locality : North Pacific Ocean. Latitudes 20° and 30° north j 

 longitudes 149° and 145° west. Collected May 19 and June 28, 1873. 



