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Terminal appendages of anterior maxillipeds not sensory. Natatory legs with the 

 same number of joints in the rami as in the Diaixidce, but not nearly so elongated. 

 Last pair of legs present in both sexes, in female rather small and of simple 

 structure, in male largely developed, uniramous, left leg the largest and having 

 some of the joints conspicuously dilated. 



Remarks. The type of this family is the genus Stephos of Scott (= Moe- 

 lianus, Giesbr.), which was placed by Dr. Giesbrecht within his subfamily Claufio- 

 calanince, answering to the family Pseudocalanidce of the present account. I think, 

 however, that this arrangement is quite inadmissible, since this genus differs in 

 several points very essentially from the other genera of this family. The uniform 

 structure of the anterior antennae and the oral parts in both sexes proves it in 

 reality to belong to the section Isokerandria, as here defined. The present family 

 likewise differs rather materially from the Diaixidce in the structure of the anterior 

 maxillipeds, as also in the presence of distinctly developed, though small, legs of 

 the 5th pair in the female, and the structure of these legs in the male. In addi- 

 tion to the typical genus, Stephos Scott, another apparently nearly-allied genus, 

 Parastephos, will be described below. 



Gen. 16. StephOS 1 ), Scott, 1892. 



Syn : Moebianus, 4 Giesbrecht. 



Generic Characters. Body of a rather short and compact form, with the 

 anterior division more or less tumefied. Front cut off, as it were, below, and not 

 forming any perceptible prominence. Lateral parts of last segment of rnetasome 

 rounded off, sometimes lamellarly expanded. Urosome comparatively short; caudal 

 rami likewise short, but with the apical setse rather elongated. Anterior antennae 

 moderately slender, 24-articulate, with scattered bristles in front. Posterior 

 antennae with the outer ramus longer than the inner. Anterior lip remarkably 

 prominent. Mandibles strong, with the masticatory part somewhat expanded, 

 outermost denticle not very different from the others ; palp with the inner ramus 

 fully as large as the outer. Anterior maxillipeds comparatively small; posterior 

 ones well developed, with the terminal part elongated and not reflexed. Natatory 

 legs with the rami normal in both sexes. Last pair of legs in female 3-articulate, 



x ) I do not consider it necessary to change this name to Stephus, as proposed hy Dr. 

 Gieshrecht, since there are several generic names generally admitted in Zoology, which have 

 a similar Greek termination (Rhinoceros, Aceros, etc.) 



