I D O T M I D E A. 707 



Plate 46, figure 8a, animal, enlarged; b, inner antennae; c, outer 

 antennae ; d y mandible, in one view ; d', extremity of the same, in 

 another view ; e, inner maxilla ; /, maxilliped ; g, leg of fourth pair. 



From near Vina del Mar, three leagues north of Valparaiso, Chili; 

 found on an Asterias. 



Length, one-fifth of an inch. Colour, yellowish-white. The head 

 is rather longer than the first thoracic segment; the front margin is a 

 little concave either side of the prominence that forms its centre, and 

 from beneath this part the tentacles proceed. The thoracic segments 

 are all short, and the last four are a little separated on either side. 

 There is a slight pubescence and a few very short hairs at the extre- 

 mity of the abdomen. The exterior plates cover completely the 

 abdomen below; margins of the plates hirsute. The antennae are 

 stoutish, and bear a few short hairs. The legs are all rather short. 



Genus CLEANTIS, Dana. 



Antennce externce vdlde longiores, non geniculates, 5—6-articulatce, fla- 

 gello articulato non con/ectce, articulo ultimo oblongo. Pedes quarti 

 tertiis valde breviores; parium quaUior ultimorum sensim longitudine 

 increscentes. Abdominis opercula laminam internum parvidam ad 

 articulationem gerentia. 



Outer antennae much the longer, not geniculate, five to six-jointed, 

 without a flagellum. Feet of fourth pair very much shorter than 

 third; last four pairs gradually increase in length. Outer abdo- 

 minal plates or opercula having a small lamina attached inside at 

 the articulation. 



The body of the species of Cleantis collected is slender linear, and 

 the legs increase from the first to the third pair, and again from the 

 fourth to the seventh, the third and seventh pairs being the longest, 

 and the fourth very short. The outer antennae have a single joint in 

 place of a flagellum, and are very much longer than the inner. 



The mandibles have two processes besides the terminal; the ter- 

 minal is rather slender and imperfectly dentated at apex ; the second, 

 just below, is equally slender and alike dentated; the third, corre- 



