ilii; lager thai the first pair of Men cd as in ihe. e 
Eo "^ 1 * 
3i us 3. ANA, Dana, Similar to Corycous but etm the sec- 
QU dd 
m. Genus S Ema D onemS dn. Body much depressed ; antennae 
as in Coryceus ; abdomen 5 or 6-jointed, the basal joint in the female 
| abruptly narrower than the thorax, and having a pair of short appen- 
dages; external ovaries two. 
Family 5. BIAGIO, Antenne as in Setella; external ovary 
single. 
Genus l. Minacia, Dana. Body not depressed, nearly as in the 
Arpactide, the abdomen 5 or 6-jointed and not abruptly narrower than 
| the thorax; anterior antennz nearly as in Setella, with a short ap- 
| pendage near the middle ; second pair of antennz terminating in a few 
movable setze; beak with two cultriform appendages ; first pair of legs 
subcheliform. 
'T'he distinctions in the above genera rest to a considerable ex- 
| tent upon the use of different organs for grasping in the union 
of the sexes. In Cyclops and Arpactus, both anterior antennze 
of the male are subcheliform for this purpose; in Pontella and 
Candacia, the nght antenna and night posterior thoracic leg is 
thus modified in the male; in Z'uchirus, both posterior- thoracic 
legs are very much elongated ;: in Calanus, the first pair of legs 
are long and have an outward lateral motion for the purpose ; 
m Corycceus the second. pair of antenne subserves this end, and 
in Antaria the first pair of legs are large and subcheliform ; in 
Setella the same end appears to be secured by the first pair of 
natatories. | 
'The genera of Calanidz differ also in the relative development 
of the maxillipeds and first pair of legs. In Pontella, Acartia, 
and Scribella, the maxillipeds are largest. In Pontella and. Acar- 
tia, they are straight, with long setulose setze directed forward so 
as to form a kind of scoop-net. In Sceribella they are flexed like 
theletter L... In Calanus, E'uchirus and Candacia, the first pair 
of legs are larger than the maxillipeds; in Calanus they are long 
regard to their nature which I can suggest, is their possible connection with phos- 
phorescence. But such an arrangement for this end is not probable; and more- 
over I was never satisfied that the species were phosphorescent. 
