578 



with the anterior lobe much deeper than the posterior. Cephalon without 

 any rostrum, frontal part more or less produced, postantennal corners well 

 marked. Eyes generally distinctly developed. Antennae elongated, the 

 superior ones with the accessory appendage either very small or wanting; the 

 inferior ones generally stronger than the superior, especially in the male. 

 Oral parts on the whole normal. Gnathopoda more or less unequal, the 

 posterior ones being the larger, and sometimes enormously developed in 

 the male. Pereiopoda not very slender, the 3 posterior pairs generally 

 strongly reflexed, with the dactylus iinguiform, and in tlie antepenultimate 

 ])air, as a ride, inverted. Last pair of uropoda rather strong, bi-ramous or uni- 

 ramous, rami shorter than the basal part, and more or less distinctly hooked. 

 Telson very small. 



RemarJcs. — The present family, as defined here, is nearly allied to 

 the preceding one, there being apparentl}^ several connecting links between 

 the two. Thus, as stated above, the genus Amphitho'e exhiliits some points of 

 agreement with the genus Photis, and the genus Ischi/rocerus would seem to 

 resemble in many particulars the genera Gammaropsis and Podoceropsis. The 

 only prevailing characteristic distinguishing this family from the preceding 

 one, is the peculiar structure of the last pair of uropoda, the rami of which 

 are more or less conspicuously hooked. This feature, which sometimes also 

 extends to the telson, .stands in close relation to the habits of the several 

 species comprised within this family, they being all true domicolous forms. 

 Boeck divided the family into two subfamilies, viz, Amphithoince and Podocerince. 

 As I am at present not disposed to adopt any subfamilies, I have comlnned 

 both. To the fauna of Norway belong 8 genera, to be described below. 



Gen. 1. Amphithoe, Leach, 1813. 



Syn: Cymadusa, Savigny. 

 > Anisopus, Templeton. 



Body slender and compressed, with the coxal jdates of moderate size 

 and closely contiguous, 5th pair with the anterior lobe very large, forming 

 together with the jireceding pairs a continuous series. Cephalon rather deep, 

 with the frontal part but little produced. Eyes small, liut distinct. Superior 

 antennae without any accessory appendage, and, as a rule, longer than the 

 inferior; the latter much stronger in male than in female. Buccal area 



