OAMMAUIU-K. 99 



3. Phoxus plumosus. (I'l.vtk XVI. tig. 3.) 



rboxus jiluinosiis, Kn'ii/cr, Tidskr. vol. iv. p. IHO. 



Spence Bate, St/iiops. lirit. Ainph., Ann. Nat. Hist, Feb. 1857 ; 

 Report lirit. Assoc. IHoH. 



niiite, Hist, of Brit. Cru.st. p. 173. 

 Phoxu3 fiisilbrniis, Stitnjtson, Mar. Invert. Grand Manan, p. 57. 



The anterior portion of the cephalon more obtuse than in P. Hol- 

 huUi. Superior antenna; long, the peduncle reaching consider- 

 ably beyond the rostrum; flageUum subequal, not longer than 

 the peduncle : first segment of the peduncle very long and broad ; 

 second nan-ow, being narrower at the posterior than at the ante- 

 rior extremity ; tliird still narrower and scarcelj- as long : the 

 inferior margin of each joint is fringed with long and strong hairs, 

 which spread themselves as from a common centre ; those on the 

 basal segment are biarticulate and binishlike. The inferior antennae 

 are scarcely as long as the superior ; the penultimate joint of the 

 peduncle is longer than either of the othei-s, and is developed 

 inferiorly into an extended squamiform process fringed with plu- 

 mose ciha, as is also the anterior margin of the same joint; fla- 

 gellum shorter than the peduncle, with the first joint as long as 

 two or three of the succeeding. First pair of gnathopoda having 

 the propodos tapering ; palm obHquc. Second pair somewhat 

 smaller than the fii'st. Pereiopoda having the dactylos quite as 

 long as the propodos, and the lateral spines (which appear to 

 be moveable), originating at the extremity of the propodos, as 

 long as the dactylos, against which they appear to have the 

 power of being compressed into a corresponding groove on each 

 side. Coxa5 of the gnathopoda and two anterior pairs of pereio- 

 poda as deep as the body of the animal, the inferior margin of 

 each being fiinged with a single row of plumose hairs. Third 

 pair of pereiopoda having the bases not developed into a squami- 

 form plate ; fomlh pair ha^•ing the bases but slightly so, and 

 the entire limb considerably produced in Icngtli ; the dactylos 

 as long as the propodos, with its extremity styliform. Fifth pair 

 ha^•ing the basos largely developed into a squamiform plate, 

 somewhat oval in form and pointed at the lower extremity, and 

 serrated along the posterior margin ; from the intermediate de- 

 pressions arises a small cilium ; the dactylos long, straight and 

 slender, reaching but little beyond the width of the squaniifonn 

 basos. The plcopoda terminate subequally. TcLson double, not so 

 long as the peduncle of the posterior plcopoda. Colour corneous 

 and transparent. Hairs upon the animal generally plumose. The 

 .structure of the tissue under the microscope is minutely granular. 



Length about ^ths of an inch. 



11 2 



