144 



molar expansion distinctly developed, palp of moderate size having the 2 outer 

 joints not very much expanded. First pair of maxillae with the palp very 

 small, uniarticulate, and tipped by a few slender spines; 2nd pair with the 

 lobes nearly equal-sized. Maxillipeds witli the masticatory lobe scarcely 

 larger than the basal one and armed with a series of curved spines increasing 

 in length distally, palp well-developed, with the penultimate joint regular 

 oval, dactylus slender. Griiathopoda more or less unequal in size, the posterior 

 ones being the larger. Antepenultimate pair of pereiopoda with the basal 

 joint laminarly expanded; last pair with the basal joint very large, clypei- 

 form. Last pair of uropoda in female with the inner ramus naked, mucroni- 

 form, and much shorter than the outer; those in male much larger, with 

 both rami well-developed, lanceolate, and edged with ciliated setse. Lobes 

 of telson rather narrow, especially in the male. 



Remarks. The present genus, originally established by Kroyer, 

 constitutes the type of the family. The name Phoxus, proposed by that author, 

 having however been preemployed in the Entomology, the Rev. Mr. Stebbing 

 has substituted that of Plwxoceplialus, and accordingly the name of the family 

 must be changed from Plioxidce to Plioxoceplialidce. The genus comprises but 

 a single northern species; for the 2 forms formerly referred by the author 

 to that genus, I now regard as belonging to distinct, though nearly allied 

 genera. Of exotic species, the Rev. Mr. Stebbing has described 2 from the 

 Challenger Expedition as P. ~bassi and P. Kergudeni, both only in the male 

 sex, and Dr. Chevreux has added another species, P. maculatus from the 

 Expedition of Hirondelle. 



1. Phoxocephalus Holbolli (Kroyer). 



(Fl. 49). 



Phoxus Holbolli, Kroyer, Nat. Tidsskr. 1 E., p. 157. 

 Syn: Phoxus Kroyeri, Stirnpson. 



Body quite glabrous and rather high in proportion to its breadth. 

 Cephalon about the length of the 3 anterior segments of mesosome combined, 

 upper face nearly plain, hood acute triangular, reaching about to the end of 

 the peduncle of the superior antennae, postantennal corners nearly right- 

 angled. First pair of coxal plates but very little expanded distally and 

 scarcely different in form from the 2 succeeding ones, all 3 pairs oblong 

 quadrangular in form, with a series of about 10 simple bristles on the 

 posterior half of the distal edge; 4th pair scarcely broader in its outer part 

 than at the base, obliquely truncated posteriorly and exhibiting a somewhat 

 projecting angle above the middle. Last pair of epimeral plates of metasome 



