571 



Amphithoe pygmma of Lilljeborg is identical with this form. From the 2 

 succeeding species it may be easily distinguished by the comparatively 

 strongly built antennae and pereiopoda, the less produced lateral corners of 

 the cephalon, and the structure of the gnathopoda in the two sexes. 



Occurrence. — I have met with this species in several places on the 

 Norwegian coast, from Jsederen up to Finmark (Vardo), in dejjths varying 

 from 20 to 50 fathoms. It is a true domicolous form, constructing for itself 

 abodes of mud, whicli are generally fastened to the stems of Hydroida. 



Bistrihtdion. — Greenland (Kroyer), Iceland (Torell), Kattegat (Meinert). 



10. Photis longicaudata, (Sp. Bate). 



(PI. 203, fig, 1). 



Eiscladus lonfjicmulatus, Sp. Bate, Brit, sessile-eyed Crust. I, )). 412- 



Syn: Photis Liitkeni, Boeck. 



Body somewhat more slender and less deep than in the preceding 

 species. Cephalon fully as long as the first 2 segments of mesosome com- 

 bined, frontal part rather produced, with the lateral corners greatly project- 

 ing, forming narrowly rounded lobes. Anterior pairs of coxal plates but 

 little deeper than the corresponding segments, 1st pair scarcely tapering 

 distally, 5th pair with the anterior lobe narrowly roiinded at the tip. Last 

 pair of epimeral plates of metasome rounded at the lateral corners. Eyes 

 very small, rounded, placed at the very tip of the lateral lobes of the 

 cephalon. Antennae much more slender than in the type species, and some- 

 what less densely setous ; the sujierior ones exceeding half the length of the 

 ^^o'b'' .joints of the peduncle about as in P. Eeinhardd, flagellum longer than 

 tlie last 2 peduncular joints combined. Inferior antennae scarcely shorter 

 than the superior, and having the antepenultimate joint of the peduncle 

 unusually narrow and elongated, flagellum about the length of the last 2 

 peduncular joints combined. Gnathopoda less strongly built than in the 

 preceding species; the anterior ones having the carpus scarcely expanded 

 below, propodos subtriangitlar in form, with the palm rather oblique. 

 Posterior gnathopoda in male considerably larger than the anterior, with the 

 propodos rather expanded, forming below a projecting angle defining the 

 palm inferiorly, the latter somewhat excavated in the middle, and exhibiting, 

 on either side of the excavation, a slight angular projection. Pereiopoda 

 mucli more slender than in P. Eeinhardi; the 2 anterior pairs with the propodal 

 joint very narrow, and neaxdy twice as long as the carpal one, last paii' 



