STOMOPODA . M YSIDJE. 



GENUS MYSIS, Latr. 



Cancer. Muller, Otho, Fabr. 



Mysis. Latr. Lam. Leach, Edw. 



Generic character. — External antennce inserted beneath the in- 

 ternal, the first joint giving attachment to a laminar appendage, 

 similar to that in the Pala^monidce, which is much elongated and 

 ciliated on the inner margin ; the two succeeding joints of the pe- 

 duncle slender and cylindrical, the terminal filament filiform, and 

 longer than the internal antenna;, which are inserted beneath the 

 eye, near the median line, and have two terminal filaments. Pedi- 

 pal20s consisting of two pairs entirely pediform. The first pair short, 

 composed of three distinct branches ; the internal portion pediform, 

 of five joints, hairy, and doubled upon itself in front of the mouth; 

 the middle branch or palp elongated, and composed of numerous 

 articulations ; the basilar joint very large, with a ciliated strap- 

 shaped process on each side ; the third or external branch, or fla- 

 belliform appendage, is represented by a semimembranous scale 

 directed upwards, and lying under the margin of the carapace. 

 Second pair of j^edipalps of the same form, but wanting the fla- 

 belliform appendage. Feet of six pairs, composed of corresponding 

 elements with the external pedipalps and five pairs of feet in the 

 DECAPODA ; each consisting of two branches, decreasing in length 

 from before backwards, and formed for swimming ; the first four 

 pairs have no flabelliform appendage ; the last two are furnished 

 with it. This part in the male is very small, but in the female it 

 is greatly developed, and forms on each side a broad plate bent un- 

 der the sternum, the two thus forming a pouch, in which the eggs 

 are first deposited, and within which the young are secluded, and 

 pass the early period of their life. Carapace covering only the 



