94 Transactions.— Zoology. 
footjaws broad, sete numerous; posterior pair much elongated, terminal 
portion five-jointed, and furnished with several sete of moderate length. 
Five pairs of swimming feet, all two-branched, and each branch of the first 
four pairs three-jointed and almost similar; fifth pair with both branches 
three-jointed in the female, but outer branch two-jointed in male, with a 
long terminal eurved (apparently prehensile) claw, inner branch some- 
what rudimentary, one-jointed. Ovisac single, borne in front of the 
abdomen. 
It is with some hesitation that I advance this new genus, but as the 
chief systematists who have studied the Calanide treat the structure of the 
inner branches of the swimming feet as of primary importance in the classi- 
fication of the genera, no other course was open to me. The genus belongs 
to the same section as Isias (Boeck), and Centropages (Kréyer). The former 
is its nearest ally, but differs in having the inner branch of the fifth pair of 
feet in the female one-jointed, while in the male the outer branch consists 
of two, and the inner of one or two joints. In Centropages, the strong 
bristles on the anterior footjaws point to its affinity with the sub-family 
Pontelling, and the outer branch of the fifth pair of feet in the male is 
developed into a powerful grasping claw on the right side only, while the 
inner branch is normally three-jointed. 
1. Boeckia triarticulata, sp. nov. Pl. VI., fig. 1. 
Body elongated, rounded above, last thoracic segment produced into a 
strong spine on its infero-posterior margin. Anterior antenns almost as 
long as the body: that of. the male on the right side swollen in the middle, 
hinged between the 19th and 20th joints, and bearing denticulated plates 
on the inner face of the 18th and 19th joints above, and on the 20th joint 
below the hinge; spines and setw rather few. Fifth pair of feet in the 
female somewhat similar to preceding pairs, but with the middle joint of 
the outer branch produced internally into a strong toothed spine (in this 
respect resembling to some extent Centropages typicus), inner branch rather 
reduced in size ; in the male the outer branch is distended and two-jointed, 
with a long terminal curved claw, which is longer and more slender on the 
left than on the right side. Caudal segments about as long as last abdo- 
minal segments, and bearing five densely plumose rigid sete, which are 
shorter than the abdomen. 
panes (including caudal sete) i1; inch; spread of anterior antenne, 
Hab. This interesting species was obtained in shingle-pits (fresh 
water) at Eyreton, in the North Canterbury District, by Mr. Chas. Chilton. 
Most of the specimens are reddish in colour, but the colouration is very 
variable both in intensity and localization. 
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PROMUS a emi E TAE 
