108 H. J. HANSEN. 
(3) Basal joint of antennule expanded, protruding as an 
exceedingly large, free, horizontal, angular plate in front of 
the head. Both sexes similar, without processes; end of 
abdomen with a semicircular or triangular notch ; urp. with 
the rami well developed, lamellar. specially fourth, fifth 
and sixth pairs of thoracic legs short and very thick, much 
thicker than the anterior pairs. Mouth-parts similar in both 
sexes ; marsupial lamelle as in Scutuloidea, but the propa- 
gation unknown. 
(6) Amphoroidea (M.-Edw.). 
(b) Exp. of plp.? with an articulation rather near the end. 
(a) Head of normal size. Basal joint of antennulee has its 
distal posterior angle produced into an acute process lying 
close to the hind margin of second joint. Abdomen with a 
well-developed notch. Exp. of urp. about as large as or 
much larger than endp. 
(t) Male without any mesial process on sixth thoracic seg- 
ment. Female with the abdominal notch semicircular, the 
mouth-paris strongly metamorphosed (the mandibles coal- 
esced with the head). 
(§) Male has paired denticles in the abdominal notch, urp. 
strongly altered, with exp. very elongate, curved. Female 
has the brood in internal pouches. 
(7) Paracerceis (n. gen.). 
($$) Male has a mesial lobe, but no paired denticles in the 
abdominal notch ; urp. not much altered, their exp. straight. 
Female carries the brood in the marsupium itself. 
(8) Cerceis (M.-Edw.). 
(tt) Male with a large mesial process on sixth thoracic 
segment. (Female unknown.) 
(9) Haswellia (Miers). 
(3. Head small, narrow in proportion to largest breadth of 
thorax. Basal joint of antennule without process from the 
distal posterior angle. End of abdomen feebly emarginate. 
